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81 results on '"Börst, H."'

2. The technical performance of the HEGRA system of imaging air Cherenkov telescopes

Author

Pühlhofer, G, Bolz, O, Götting, N, Heusler, A, Horns, D, Kohnle, A, Lampeitl, H, Panter, M, Tluczykont, M, Aharonian, F, Akhperjanian, A, Beilicke, M, Bernlöhr, K, Börst, H, Bojahr, H, Coarasa, T, Contreras, J.L, Cortina, J, Denninghoff, S, Fonseca, M.V, Girma, M, Heinzelmann, G, Hermann, G, Hofmann, W, Jung, I, Kankanyan, R, Kestel, M, Konopelko, A, Kornmeyer, H, Kranich, D, Lopez, M, Lorenz, E, Lucarelli, F, Mang, O, Meyer, H, Mirzoyan, R, Moralejo, A, Ona-Wilhelmi, E, Plyasheshnikov, A, de los Reyes, R, Rhode, W, Ripken, J, Rowell, G, Sahakian, V, Samorski, M, Schilling, M, Siems, M, Sobzynska, D, Stamm, W, Vitale, V, Völk, H.J, Wiedner, C.A, and Wittek, W

Published
2003
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3. Limits on the TeV flux of diffuse gamma rays as measured with the HEGRA air shower array

Author

Aharonian, F.A., Akhperjanian, A.G., Barrio, J.A., Bernlöhr, K., Bojahr, H., Bolz, O., Börst, H., Contreras, J.L., Cortina, J., Denninghoff, S., Fonseca, V., Gebauer, H.J., Gonzalez, J.C., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Ibarra, A., Iserlohe, C., Jung, I., Kankanyan, R., Kestel, M., Kettler, J., Kohnle, A., Konopelko, A., Kornmayer, H., Kranich, D., Krawczynski, H., Lampeitl, H., Lopez, M., Lorenz, E., Lucarelli, F., Magnussen, N., Mang, O., Meyer, H., Mirzoyan, R., Moralejo, A., Oña, E., Padilla, L., Panter, M., Plaga, R., Plyasheshnikov, A., Prahl, J., Pühlhofer, G., Rauterberg, G., Rhode, W., Röhring, A., Rowell, G.P., Sahakian, V., Samorski, M., Schilling, M., Schröder, F., Siems, M., Stamm, W., Tluczykont, M., Völk, H.J., Wiedner, C., and Wittek, W.

Published
2002
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4. Variations of the TeV energy spectrum at different flux levels of Mkn 421 observed with the HEGRA system of Cherenkov telescopes

Author

Aharonian, F., Akhperjanian, A., Beilicke, M., Bernlöhr, K., Börst, H., Bojahr, H., Bolz, O., Coarasa, T., Contreras, J., Cortina, J., Costamante, L., Denninghoff, S., Fonseca, V., Girma, M., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Jung, I., Kankanyan, R., Kestel, M., Kettler, J., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Krawczynski, H., Lampeitl, H., Lopez, M., Lorenz, E., Fabrizio Lucarelli, Mang, O., Meyer, H., Mirzoyan, R., Milite, M., Moralejo, A., Ona, E., Panter, M., Plyasheshnikov, A., Pühlhofer, G., Rauterberg, G., Reyes, R., Rhode, W., Ripken, J., Rowell, G., Sahakian, V., Samorski, M., Schilling, M., Siems, M., Sobzynska, D., Stamm, W., Tluczykont, M., Völk, H. J., Wiedner, C. A., Wittek, W., and Remillard, R. A.

Subjects
Physics, Photon, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics (astro-ph), Mid infrared, FOS: Physical sciences, HEGRA, Astronomy and Astrophysics, Astrophysics, Power law, Spectral line, Space and Planetary Science, Energy spectrum, Cherenkov radiation, Background radiation
Abstract

The nearby BL Lacertae (BL Lac) object Markarian~421 (Mkn~421) at a red shift z=0.031 was observed to undergo strong TeV Gamma-ray outbursts in the observational periods from December 1999 until May 2001. The time averaged energy spectrum is well described by a power law with an exponential cut-off energy at 3.6(+0.4-0.3)_{stat}(+0.9-0.8)_{sys} TeV. The energy spectra derived for different average flux levels ranging from 0.5 to 10 * 10^{-11}ph/cm**2/s follow a clear correlation of photon index and flux level. Generally, the energy spectra are harder for high flux levels. From January to April 2001 Mkn~421 showed rapid variability (doubling time as short as 20 minutes), accompanied with a spectral hardening with increasing flux level within individual nights. For two successive nights (MJD 51989-51991, March 21-23,2001), this correlation of spectral hardness and change in flux has been observed within a few hours. The cut-off energy for the Mkn~421 TeV spectrum remains within the errors constant for the different flux levels and differs by 2.6+/-0.6_stat+/-0.6_sys TeV from the value determined for Mkn~501. This indicates that the observed exponential cut-off in the energy spectrum of Mkn~421 is not solely caused by absorption of multi-TeV photons by pair-production processes with photons of the extragalactic near/mid infrared background radiation., Comment: 12 pages, 9 figures, submitted to Astronomy&Astrophysics

Published
2002
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5. The 2(nd) Berlin BedRest Study: protocol and implementation

Author

Belavy DL 1, Bock O 1, Börst H 1, Armbrecht G 1, Gast U 1, Degner C 1, Beller G 1, Soll H 2, Salanova M 3, Habazettl H. 4, Heer M 5, de Haan A 6, Stegeman DF 6, 7, Cerretelli P 8, Blottner D 3, Rittweger J 9, Gelfi C 10, Kornak U 11, and Felsenberg D 1

Subjects
Countermeasures, Spaceflight, Microgravity, Inactivity, Exercise
Abstract

Long-term bed-rest is used to simulate the effect of spaceflight on the human body and test different kinds of countermeasures. The 2nd Berlin BedRest Study (BBR2-2) tested the efficacy of whole-body vibration in addition to high-load resisitance exercise in preventing bone loss during bed-rest. Here we present the protocol of the study and discuss its implementation. Twenty-four male subjects underwent 60-days of six-degree head down tilt bed-rest and were randomised to an inactive control group (CTR), a high-load resistive exercise group (RE) or a high-load resistive exercise with whole-body vibration group (RVE). Subsequent to events in the course of the study (e.g. subject withdrawal), 9 subjects participated in the CTR-group, 7 in the RVE-group and 8 (7 beyond bed-rest day-30) in the RE-group. Fluid intake, urine output and axiallary temperature increased during bed-rest (p=.17). Body weight changes differed between groups (p

Published
2010

6. Observations of H1426+428 with HEGRA -- Observations in 2002 and reanalysis of 1999&2000 data

Author

Aharonian, F., Akhperjanian, A., Beilicke, M., Bernlöhr, K., Börst, H. -G, Bojahr, H., Bolz, O., Coarasa, T., Contreras, J. L., Juan Cortina, Costamante, L., Denninghoff, S., Fonseca, M. V., Girma, M., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Jung, I., Kankanyan, R., Kestel, M., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Lampeitl, H., Lopez, M., Lorenz, E., Lucarelli, F., Mang, O., Mazine, D., Meyer, H., Mirzoyan, R., Moralejo, A., Ona-Wilhelmi, E., Panter, M., Plyasheshnikov, A., Prahl, J., Pühlhofer, G., Los Reyes, R., Rhode, W., Ripken, J., Rowell, G., Sahakian, V., Samorski, M., Schilling, M., Siems, M., Sobzynska, D., Stamm, W., Tluczykont, M., Vitale, V., Völk, H. J., Wiedner, C. A., and Wittek, W.

Subjects
Physics, Astrophysics::High Energy Astrophysical Phenomena, Flux, HEGRA, Astronomy and Astrophysics, Astrophysics, Spectral line, Wavelength, Extragalactic background light, Space and Planetary Science, Absorption (electromagnetic radiation), Cherenkov radiation, BL Lac object
Abstract

The HEGRA system of imaging air Cherenkov telescopes has been used to observe the BL Lac object H1426+428 ($z=0.129$) for 217.5 hours in 2002. In this data set alone, the source is detected at a confidence level of $5.3~\sigma$, confirming this object as a TeV source. The overall flux level during the observations in 2002 is found to be a factor of $\approx 2.5$ lower than during the previous observations by HEGRA in 1999&2000. A new spectral analysis has been carried out, improving the signal-to-noise ratio at the expense of a slightly increased systematic uncertainty and reducing the relative energy resolution to $\Delta E/E\le 12 %$ over a wide range of energies. The new method has also been applied to the previously published data set taken in 1999 and 2000, confirming the earlier claim of a flattening of the energy spectrum between 1 and 5 TeV. The data set taken in 2002 shows again a signal at energies above 1 TeV. We combine the energy spectra as determined by the CAT and VERITAS groups with our reanalyzed result of the 1999&2000 data set and apply a correction to account for effects of absorption of high energy photons on extragalactic background light in the optical to mid infrared band. The shape of the inferred source spectrum is mostly sensitive to the characteristics of the extragalactic background light between wavelengths of 1 and 15~$\mu$m, Comment: 12 pages, 4 Figures, submitted to A&A

Published
2003

7. The 2nd Berlin BedRest Study: protocol and implementation

Author

Belavý, D.L., Bock, O., Börst, H., Armbrecht, G., Gast, U., Degner, C., Beller, G., Soll, H., Salanova, M., Habazettl, H., Heer, M., de Haan, A., Stegeman, D.F., Cerretelli, P., Blottner, D., Rittweger, J., Gelfi, C., Kornak, U., Felsenberg, D., Belavý, D.L., Bock, O., Börst, H., Armbrecht, G., Gast, U., Degner, C., Beller, G., Soll, H., Salanova, M., Habazettl, H., Heer, M., de Haan, A., Stegeman, D.F., Cerretelli, P., Blottner, D., Rittweger, J., Gelfi, C., Kornak, U., and Felsenberg, D.

Abstract

Long-term bed-rest is used to simulate the effect of spaceflight on the human body and test different kinds of countermeasures. The 2nd Berlin BedRest Study (BBR2-2) tested the efficacy of whole-body vibration in addition to high-load resisitance exercise in preventing bone loss during bed-rest. Here we present the protocol of the study and discuss its implementation. Twenty-four male subjects underwent 60-days of six-degree head down tilt bed-rest and were randomised to an inactive control group (CTR), a high-load resistive exercise group (RE) or a high-load resistive exercise with whole-body vibration group (RVE). Subsequent to events in the course of the study (e.g. subject withdrawal), 9 subjects participated in the CTR-group, 7 in the RVE-group and 8 (7 beyond bed-rest day-30) in the RE-group. Fluid intake, urine output and axiallary temperature increased during bed-rest (p < .0001), though similarly in all groups (p > or = .17). Body weight changes differed between groups (p < .0001) with decreases in the CTR-group, marginal decreases in the RE-group and the RVE-group displaying significant decreases in body-weight beyond bed-rest day-51 only. In light of events and experiences of the current study, recommendations on various aspects of bed-rest methodology are also discussed.

Published
2010

12. Monthly oral ibandronate 150 mg improves significantly bone density and structure measured in Vivo by Micro-CT at distal tibia in postmenopausal women with mild osteoporosis

Author

Börst, H., primary, Bock, O., additional, Beller, G., additional, Kratzsch, M., additional, Degner, C., additional, Profittlich, H., additional, Kalbow, M., additional, Armbrecht, G., additional, Martus, P., additional, Glaab, J., additional, and Felsenberg, D., additional

Published
2010
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14. Observations of 14 young open star clusters with the HEGRA system of Cherenkov telescopes

Author

Aharonian, F., primary, Akhperjanian, A., additional, Beilicke, M., additional, Bernlöhr, K., additional, Börst, H.-G., additional, Bojahr, H., additional, Bolz, O., additional, Coarasa, T., additional, Contreras, J. L., additional, Cortina, J., additional, Denninghoff, S., additional, Fonseca, M. V., additional, Girma, M., additional, Götting, N., additional, Heinzelmann, G., additional, Hermann, G., additional, Heusler, A., additional, Hofmann, W., additional, Horns, D., additional, Jung, I., additional, Kankanyan, R., additional, Kestel, M., additional, Konopelko, A., additional, Kornmeyer, H., additional, Kranich, D., additional, Lampeitl, H., additional, Lopez, M., additional, Lorenz, E., additional, Lucarelli, F., additional, Mang, O., additional, Meyer, H., additional, Mirzoyan, R., additional, Moralejo, A., additional, Ona-Wilhelmi, E., additional, Panter, M., additional, Plyasheshnikov, A., additional, Pühlhofer, G., additional, de los Reyes, R., additional, Rhode, W., additional, Ripken, J., additional, Rowell, G., additional, Sahakian, V., additional, Samorski, M., additional, Schilling, M., additional, Siems, M., additional, Sobzynska, D., additional, Stamm, W., additional, Tluczykont, M., additional, Vitale, V., additional, Völk, H. J., additional, Wiedner, C. A., additional, and Wittek, W., additional

Published
2006
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15. Search for TeV gamma ray emission from the Andromeda galaxy

Author

Aharonian, F. A., primary, Akhperjanian, A. G., additional, Beilicke, M., additional, Bernlöhr, K., additional, Bojahr, H., additional, Bolz, O., additional, Börst, H., additional, Coarasa, T., additional, Contreras, J. L., additional, Cortina, J., additional, Denninghoff, S., additional, Fonseca, V., additional, Girma, M., additional, Götting, N., additional, Heinzelmann, G., additional, Hermann, G., additional, Heusler, A., additional, Hofmann, W., additional, Horns, D., additional, Jung, I., additional, Kankanyan, R., additional, Kestel, M., additional, Kettler, J., additional, Kohnle, A., additional, Konopelko, A., additional, Kornmeyer, H., additional, Kranich, D., additional, Krawczynski, H., additional, Lampeitl, H., additional, Lopez, M., additional, Lorenz, E., additional, Lucarelli, F., additional, Mang, O., additional, Meyer, H., additional, Mirzoyan, R., additional, Moralejo, A., additional, Ona, E., additional, Panter, M., additional, Plyasheshnikov, A., additional, Pühlhofer, G., additional, Rauterberg, G., additional, Reyes, R., additional, Rhode, W., additional, Ripken, J., additional, Röhring, A., additional, Rowell, G. P., additional, Sahakian, V., additional, Samorski, M., additional, Schilling, M., additional, Siems, M., additional, Sobzynska, D., additional, Stamm, W., additional, Tluczykont, M., additional, Völk, H. J., additional, Wiedner, C. A., additional, and Wittek, W., additional

Published
2003
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16. A search for TeV gamma-ray emission from SNRs, pulsars and unidentified GeV sources in the Galactic plane in the longitude range between $-2^\circ$ and $85^\circ$

Author

Aharonian, F. A., primary, Akhperjanian, A. G., additional, Beilicke, M., additional, Bernlöhr, K., additional, Bojahr, H., additional, Bolz, O., additional, Börst, H., additional, Coarasa, T., additional, Contreras, J. L., additional, Cortina, J., additional, Denninghoff, S., additional, Fonseca, V., additional, Girma, M., additional, Götting, N., additional, Heinzelmann, G., additional, Hermann, G., additional, Heusler, A., additional, Hofmann, W., additional, Horns, D., additional, Jung, I., additional, Kankanyan, R., additional, Kestel, M., additional, Kettler, J., additional, Kohnle, A., additional, Konopelko, A., additional, Kornmeyer, H., additional, Kranich, D., additional, Krawczynski, H., additional, Lampeitl, H., additional, Lopez, M., additional, Lorenz, E., additional, Lucarelli, F., additional, Mang, O., additional, Meyer, H., additional, Mirzoyan, R., additional, Moralejo, A., additional, Ona, E., additional, Panter, M., additional, Plyasheshnikov, A., additional, Pühlhofer, G., additional, Rauterberg, G., additional, Reyes, R., additional, Rhode, W., additional, Ripken, J., additional, Röhring, A., additional, Rowell, G. P., additional, Sahakian, V., additional, Samorski, M., additional, Schilling, M., additional, Siems, M., additional, Sobzynska, D., additional, Stamm, W., additional, Tluczykont, M., additional, Völk, H. J., additional, Wiedner, C. A., additional, and Wittek, W., additional

Published
2002
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17. Search for point sources of gamma radiation above 15 TeV with the HEGRA AIROBICC array

Author

Aharonian, F., primary, Akhperjanian, A., additional, Barrio, J. A., additional, Bernlöhr, K., additional, Börst, H., additional, Bojahr, H., additional, Bolz, O., additional, Contreras, J. L., additional, Cortina, J., additional, Denninghoff, S., additional, Fonseca, V., additional, Gebauer, H. J., additional, González, J., additional, Götting, N., additional, Heinzelmann, G., additional, Hermann, G., additional, Heusler, A., additional, Hofmann, W., additional, Horns, D., additional, Jung, I., additional, Kankanyan, R., additional, Kestel, M., additional, Kettler, J., additional, Kohnle, A., additional, Konopelko, A., additional, Kornmayer, H., additional, Kranich, D., additional, Krawczynski, H., additional, Lampeitl, H., additional, López, M., additional, Lorenz, E., additional, Lucarelli, F., additional, Magnussen, N., additional, Mang, O., additional, Meyer, H., additional, Mirzoyan, R., additional, Moralejo, A., additional, Oña, E., additional, Padilla, L., additional, Panter, M., additional, Plaga, R., additional, Plyasheshnikov, A., additional, Prahl, J., additional, Pühlhofer, G., additional, Rauterberg, G., additional, Röhring, A., additional, Rhode, W., additional, Rowell, G., additional, Sahakian, V., additional, Samorski, M., additional, Schilling, M., additional, Schmele, D., additional, Schröder, F., additional, Sevilla, I., additional, Siems, M., additional, Stamm, W., additional, Tluczykont, M., additional, Völk, H. J., additional, Wiedner, C. A., additional, and Wittek, W., additional

Published
2002
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18. TeV gamma rays from the blazar H 1426+428 and the diffuse extragalactic background radiation

Author

Aharonian, F., primary, Akhperjanian, A., additional, Barrio, J., additional, Beilicke, M., additional, Bernlöhr, K., additional, Börst, H., additional, Bojahr, H., additional, Bolz, O., additional, Contreras, J., additional, Cornils, R., additional, Cortina, J., additional, Denninghoff, S., additional, Fonseca, V., additional, Girma, M., additional, Gonzalez, J., additional, Götting, N., additional, Heinzelmann, G., additional, Hermann, G., additional, Heusler, A., additional, Hofmann, W., additional, Horns, D., additional, Jung, I., additional, Kankanyan, R., additional, Kestel, M., additional, Kettler, J., additional, Kohnle, A., additional, Konopelko, A., additional, Kornmeyer, H., additional, Kranich, D., additional, Krawczynski, H., additional, Lampeitl, H., additional, Lopez, M., additional, Lorenz, E., additional, Lucarelli, F., additional, Magnussen, N., additional, Mang, O., additional, Meyer, H., additional, Mirzoyan, R., additional, Moralejo, A., additional, Ona, E., additional, Padilla, L., additional, Panter, M., additional, Plaga, R., additional, Plyasheshnikov, A., additional, Pühlhofer, G., additional, Rauterberg, G., additional, Röhring, A., additional, Rhode, W., additional, Robrade, J., additional, Rowell, G., additional, Sahakian, V., additional, Samorski, M., additional, Schilling, M., additional, Schröder, F., additional, Sevilla, I., additional, Siems, M., additional, Stamm, W., additional, Tluczykont, M., additional, Völk, H. J., additional, Wiedner, C. A., additional, and Wittek, W., additional

Published
2002
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19. TeV gamma-ray observations of SS-433 and a survey of the surrounding field with the HEGRA IACT-System

Author

Aharonian, F., Akhperjanian, A., Beilicke, M., Bernlöhr, K., Börst, H.-G., Bojahr, H., Bolz, O., Coarasa, T., Contreras, J., Cortina, J., Denninghoff, S., Fonseca, V., Girma, M., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Jung, I., Kankanyan, R., Kestel, M., Kohnle, A., Konopelko, A., Kranich, D., Lampeitl, H., Lopez, M., Lorenz, E., Lucarelli, F., Mang, O., Mazin, D., Meyer, H., Mirzoyan, R., Moralejo, A., Oña-Wilhelmi, E., Panter, M., Plyasheshnikov, A., Pühlhofer, G., Reyes, R. de los, Rhode, W., Ripken, J., Rowell, G. P., Sahakian, V., Samorski, M., Schilling, M., Siems, M., Sobzynska, D., Stamm, W., Tluczykont, M., Vitale, V., Völk, H. J., Wiedner, C. A., Wittek, W., Aharonian, F., Akhperjanian, A., Beilicke, M., Bernlöhr, K., Börst, H.-G., Bojahr, H., Bolz, O., Coarasa, T., Contreras, J., Cortina, J., Denninghoff, S., Fonseca, V., Girma, M., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Jung, I., Kankanyan, R., Kestel, M., Kohnle, A., Konopelko, A., Kranich, D., Lampeitl, H., Lopez, M., Lorenz, E., Lucarelli, F., Mang, O., Mazin, D., Meyer, H., Mirzoyan, R., Moralejo, A., Oña-Wilhelmi, E., Panter, M., Plyasheshnikov, A., Pühlhofer, G., Reyes, R. de los, Rhode, W., Ripken, J., Rowell, G. P., Sahakian, V., Samorski, M., Schilling, M., Siems, M., Sobzynska, D., Stamm, W., Tluczykont, M., Vitale, V., Völk, H. J., Wiedner, C. A., and Wittek, W.

Abstract

We present results of a search for TeV γ-ray emission from the microquasar SS-433 and the surrounding region covering a ~$8^\circ$$\times$$8^\circ$field of view. Analysis of data taken with the HEGRA stereoscopic system of imaging atmospheric Čerenkov imaging telescopes reveals no evidence of steady or variable emission from any position. Observation times of over 100 h have been achieved in central parts of the field of view. We set 99% confidence level upper limits to a number of a-priori-chosen objects of interest, including SS-443 and its interaction regions, 32 pulsars, 3 supernova remnants and the GeV source GeV J1907+0537. Our upper limit of 3.2% Crab flux (for energies $E>0.8$TeV) for the eastern-lobe region e3of SS-433 permits, after comparison with X-ray fluxes, a lower limit of $B\geq19~\mu$G on the post-shocked magnetic field in this region. An ensemble upper limit at 0.3% Crab flux ($E>0.7$TeV) from a subset (11) of the 32 pulsars implies a maximum of 4.5% of the spin-down pulsar power is available for TeV γ-ray production. For one of the SNR in our FoV, 3C 396, recent Chandra observations suggest that a central pulsar-driven wind nebula may be the source of X-ray emission. Our upper limit implies that a maximum of 0.1% of the spin-down power from the central source of 3C 396 would be available for TeV γ-rays.

Published
2005
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20. A search for gamma-ray emission from the Galactic plane in the longitude range between $\mathsf{37}^\circ$ and $\mathsf{43}^\circ$

Author

Aharonian, F. A., primary, Akhperjanian, A. G., additional, Barrio, J. A., additional, Bernlöhr, K., additional, Bolz, O., additional, Börst, H., additional, Bojahr, H., additional, Contreras, J. L., additional, Cortina, J., additional, Denninghoff, S., additional, Fonseca, V., additional, Gonzalez, J. C., additional, Götting, N., additional, Heinzelmann, G., additional, Hermann, G., additional, Heusler, A., additional, Hofmann, W., additional, Horns, D., additional, Ibarra, A., additional, Iserlohe, C., additional, Jung, I., additional, Kankanyan, R., additional, Kestel, M., additional, Kettler, J., additional, Kohnle, A., additional, Konopelko, A., additional, Kornmeyer, H., additional, Kranich, D., additional, Krawczynski, H., additional, Lampeitl, H., additional, Lorenz, E., additional, Lucarelli, F., additional, Magnussen, N., additional, Mang, O., additional, Meyer, H., additional, Mirzoyan, R., additional, Moralejo, A., additional, Padilla, L., additional, Panter, M., additional, Plaga, R., additional, Plyasheshnikov, A., additional, Prahl, J., additional, Pühlhofer, G., additional, Rhode, W., additional, Röhring, A., additional, Rowell, G. P., additional, Sahakian, V., additional, Samorski, M., additional, Schilling, M., additional, Schröder, F., additional, Siems, M., additional, Stamm, W., additional, Tluczykont, M., additional, Völk, H. J., additional, Wiedner, C. A., additional, and Wittek, W., additional

Published
2001
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21. A study of Tycho's SNR at TeV energies with the HEGRA CT-System

Author

Aharonian, F. A., primary, Akhperjanian, A. G., additional, Barrio, J. A., additional, Bernlöhr, K., additional, Börst, H., additional, Bojahr, H., additional, Bolz, O., additional, Contreras, J. L., additional, Cortina, J., additional, Denninghoff, S., additional, Fonseca, V., additional, Gonzalez, J. C., additional, Götting, N., additional, Heinzelmann, G., additional, Hermann, G., additional, Heusler, A., additional, Hofmann, W., additional, Horns, D., additional, Ibarra, A., additional, Jung, I., additional, Kankanyan, R., additional, Kestel, M., additional, Kettler, J., additional, Kohnle, A., additional, Konopelko, A., additional, Kornmeyer, H., additional, Kranich, D., additional, Krawczynski, H., additional, Lampeitl, H., additional, Lorenz, E., additional, Lucarelli, F., additional, Magnussen, N., additional, Mang, O., additional, Meyer, H., additional, Mirzoyan, R., additional, Moralejo, A., additional, Padilla, L., additional, Panter, M., additional, Plaga, R., additional, Plyasheshnikov, A., additional, Prahl, J., additional, Pühlhofer, G., additional, Rauterberg, G., additional, Röhring, A., additional, Rhode, W., additional, Rowell, G. P., additional, Sahakian, V., additional, Samorski, M., additional, Schilling, M., additional, Schröder, F., additional, Stamm, W., additional, Tluczykont, M., additional, Völk, H. J., additional, Wiedner, C., additional, and Wittek, W., additional

Published
2001
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22. Evidence for TeV gamma ray emission from Cassiopeia A

Author

Aharonian, F., primary, Akhperjanian, A., additional, Barrio, J., additional, Bernlöhr, K., additional, Börst, H., additional, Bojahr, H., additional, Bolz, O., additional, Contreras, J., additional, Cortina, J., additional, Denninghoff, S., additional, Fonseca, V., additional, Gonzalez, J., additional, Götting, N., additional, Heinzelmann, G., additional, Hermann, G., additional, Heusler, A., additional, Hofmann, W., additional, Horns, D., additional, Ibarra, A., additional, Iserlohe, C., additional, Jung, I., additional, Kankanyan, R., additional, Kestel, M., additional, Kettler, J., additional, Kohnle, A., additional, Konopelko, A., additional, Kornmeyer, H., additional, Kranich, D., additional, Krawczynski, H., additional, Lampeitl, H., additional, Lopez, M., additional, Lorenz, E., additional, Lucarelli, F., additional, Magnussen, N., additional, Mang, O., additional, Meyer, H., additional, Mirzoyan, R., additional, Moralejo, A., additional, Ona, E., additional, Padilla, L., additional, Panter, M., additional, Plaga, R., additional, Plyasheshnikov, A., additional, Prahl, J., additional, Pühlhofer, G., additional, Rauterberg, G., additional, Röhring, A., additional, Rhode, W., additional, Rowell, G. P., additional, Sahakian, V., additional, Samorski, M., additional, Schilling, M., additional, Schröder, F., additional, Siems, M., additional, Stamm, W., additional, Tluczykont, M., additional, Völk, H. J., additional, Wiedner, C. A., additional, and Wittek, W., additional

Published
2001
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23. Search for a TeV gamma-ray halo of Mkn 501

Author

Aharonian, F. A., primary, Akhperjanian, A. G., additional, Barrio, J. A., additional, Bernlöhr, K., additional, Bolz, O., additional, Börst, H., additional, Bojahr, H., additional, Contreras, J. L., additional, Cortina, J., additional, Denninghoff, S., additional, Fonseca, V., additional, Gonzalez, J. C., additional, Götting, N., additional, Heinzelmann, G., additional, Hermann, G., additional, Heusler, A., additional, Hofmann, W., additional, Horns, D., additional, Ibarra, A., additional, Iserlohe, C., additional, Jung, I., additional, Kankanyan, R., additional, Kestel, M., additional, Kettler, J., additional, Kohnle, A., additional, Konopelko, A., additional, Kornmeyer, H., additional, Kranich, D., additional, Krawczynski, H., additional, Lampeitl, H., additional, Lorenz, E., additional, Lucarelli, F., additional, Magnussen, N., additional, Mang, O., additional, Meyer, H., additional, Mirzoyan, R., additional, Moralejo, A., additional, Padilla, L., additional, Panter, M., additional, Plaga, R., additional, Plyasheshnikov, A., additional, Prahl, J., additional, Pühlhofer, G., additional, Rhode, W., additional, Röhring, A., additional, Rowell, G. P., additional, Sahakian, V., additional, Samorski, M., additional, Schilling, M., additional, Schröder, F., additional, Siems, M., additional, Stamm, W., additional, Tluczykont, M., additional, Völk, H. J., additional, Wiedner, C., additional, and Wittek, W., additional

Published
2001
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24. Reanalysis of the high energy cutoff of the 1997 Mkn 501 TeV energy spectrum

Author

Aharonian, F. A., primary, Akhperjanian, A. G., additional, Barrio, J. A., additional, Bernlöhr, K., additional, Bolz, O., additional, Börst, H., additional, Bojahr, H., additional, Contreras, J. L., additional, Cortina, J., additional, Denninghoff, S., additional, Fonseca, V., additional, Gonzalez, J. C., additional, Götting, N., additional, Heinzelmann, G., additional, Hermann, G., additional, Heusler, A., additional, Hofmann, W., additional, Horns, D., additional, Ibarra, A., additional, Iserlohe, C., additional, Jung, I., additional, Kankanyan, R., additional, Kestel, M., additional, Kettler, J., additional, Kohnle, A., additional, Konopelko, A., additional, Kornmeyer, H., additional, Kranich, D., additional, Krawczynski, H., additional, Lampeitl, H., additional, Lorenz, E., additional, Lucarelli, F., additional, Magnussen, N., additional, Mang, O., additional, Meyer, H., additional, Mirzoyan, R., additional, Moralejo, A., additional, Padilla, L., additional, Panter, M., additional, Plaga, R., additional, Plyasheshnikov, A., additional, Prahl, J., additional, Pühlhofer, G., additional, Rhode, W., additional, Röhring, A., additional, Rowell, G. P., additional, Sahakian, V., additional, Samorski, M., additional, Schilling, M., additional, Schröder, F., additional, Siems, M., additional, Stamm, W., additional, Tluczykont, M., additional, Völk, H. J., additional, Wiedner, C., additional, and Wittek, W., additional

Published
2001
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25. Observation of the Monoceros Loop SNRregion with the HEGRA system of IACTs

Author

Aharonian, F. A., Akhperjanian, A. G., Beilicke, M., Bernlöhr, K., Börst, H.-G., Bojahr, H., Bolz, O., Coarasa, T., Contreras, J. L., Cortina, J., Denninghoff, S., Fonseca, M. V., Girma, M., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Jung, I., Kankanyan, R., Kestel, M., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Lampeitl, H., Lopez, M., Lorenz, E., Lucarelli, F., Mang, O., Meyer, H., Mirzoyan, R., Moralejo, A., Ona-Wilhelmi, E., Panter, M., Plyasheshnikov, A., Pühlhofer, G., Reyes, R. de los, Rhode, W., Ripken, J., Rowell, G., Sahakian, V., Samorski, M., Schilling, M., Siems, M., Sobzynska, D., Stamm, W., Tluczykont, M., Vitale, V., Völk, H. J., Wiedner, C. A., Wittek, W., Aharonian, F. A., Akhperjanian, A. G., Beilicke, M., Bernlöhr, K., Börst, H.-G., Bojahr, H., Bolz, O., Coarasa, T., Contreras, J. L., Cortina, J., Denninghoff, S., Fonseca, M. V., Girma, M., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Jung, I., Kankanyan, R., Kestel, M., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Lampeitl, H., Lopez, M., Lorenz, E., Lucarelli, F., Mang, O., Meyer, H., Mirzoyan, R., Moralejo, A., Ona-Wilhelmi, E., Panter, M., Plyasheshnikov, A., Pühlhofer, G., Reyes, R. de los, Rhode, W., Ripken, J., Rowell, G., Sahakian, V., Samorski, M., Schilling, M., Siems, M., Sobzynska, D., Stamm, W., Tluczykont, M., Vitale, V., Völk, H. J., Wiedner, C. A., and Wittek, W.

Abstract

The array of 5 imaging atmospheric Čerenkov telescopes (IACTs) deployed at La Palma (Canary Islands), and operated by the HEGRA (High Energy Gamma Ray Astronomy) collaboration, was used for observations of the Monoceros Loop SNRregion for a total of about 120 hrs and 20 hrs in ON-source and OFF-source mode, respectively. The giant molecular cloud Rosette Nebula appears in the sky region, close to the south-east part of the SNRrim. Using the HEGRA system of IACTs of rather large field of view (4.3 degree in diameter), we have mapped the extended sky region of $3^\circ \times 3^\circ$associated with the Monoceros SNR/Rosette Nebula, which is centered towards the hard spectrum X-ray point source SAX J0635+533. The EGRET unidentified source of diffuse γ-ray emission (3EG J0634+0521) observed in the energy range between 100 MeV–10 GeV, was effectively in the field of view of our present observations. Also, the GeV source GeV J0633+0645 was within the available field of view. The performance of the IACTs array reveals an energy threshold of 500 GeV and an angular resolution of $0.1^\circ$for γ-rays. In what follows, we present the result of the data analysis and its physical interpretation.

Published
2004
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26. TeV γ-ray light curve and energy spectrum of Mkn 421during its 2001 flare as measured with HEGRA CT1*

Author

Aharonian, F., Akhperjanian, A., Beilicke, M., Bernlöhr, K., Börst, H. G., Bojahr, H., Bolz, O., Coarasa, J. A., Contreras, J. L., Cortina, J., Denninghoff, S., Fonseca, V., Girma, M., Goebel, F., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Jung, I., Kankanyan, R., Kestel, M., Kettler, J., Kohnle, A., Konopelko, A., Kranich, D., Krawczynski, H., Lampeitl, H., López, M., Lorenz, E., Lucarelli, F., Mang, O., Meyer, H., Mirzoyan, R., Moralejo, A., Oña-Wilhelmi, E., Paneque, D., Panter, M., Plyasheshnikov, A., Pühlhofer, G., Reyes, R. de los, Rhode, W., Ripken, J., Rowell, G., Sahakian, V., Samorski, M., Schilling, M., Schweizer, T., Sevilla, I., Siems, M., Sobczyńska, D., Stamm, W., Tluczykont, M., Tonello, N., Vitale, V., Völk, H. J., Wagner, R. M., Wiedner, C. A., Wittek, W., Aharonian, F., Akhperjanian, A., Beilicke, M., Bernlöhr, K., Börst, H. G., Bojahr, H., Bolz, O., Coarasa, J. A., Contreras, J. L., Cortina, J., Denninghoff, S., Fonseca, V., Girma, M., Goebel, F., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Jung, I., Kankanyan, R., Kestel, M., Kettler, J., Kohnle, A., Konopelko, A., Kranich, D., Krawczynski, H., Lampeitl, H., López, M., Lorenz, E., Lucarelli, F., Mang, O., Meyer, H., Mirzoyan, R., Moralejo, A., Oña-Wilhelmi, E., Paneque, D., Panter, M., Plyasheshnikov, A., Pühlhofer, G., Reyes, R. de los, Rhode, W., Ripken, J., Rowell, G., Sahakian, V., Samorski, M., Schilling, M., Schweizer, T., Sevilla, I., Siems, M., Sobczyńska, D., Stamm, W., Tluczykont, M., Tonello, N., Vitale, V., Völk, H. J., Wagner, R. M., Wiedner, C. A., and Wittek, W.

Abstract

In the first months of 2001 the AGN Mkn 421showed highly variable, strong TeV activity at flux levels frequently exceeding 1 Crab. Here we present the light curve and energy spectrum of Mkn 421as measured with the HEGRA stand alone telescope CT1. Around 30% of the data were taken under moonlight conditions. The spectrum shows a significant exponential energy cutoff at around 3.4 TeV. The results from the dark night- and the moon data are in excellent agreement with each other. A significant spectral shape variation depending on the flux level has been found. The TeV light curve is also found to be highly correlated with the X-ray light curve of the RXTE / ASM satellite, showing no significant time lag larger than 0.2 d. The derived correlation coefficient of 0.83 corresponds to a $5.2~\sigma$significance.

Published
2003
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27. Detection of TeV gamma-rays from the BL Lac 1ES 1959+650 in its low states and during a major outburst in 2002 *

Author

Aharonian, F., Akhperjanian, A., Beilicke, M., Bernlöhr, K., Börst, H.-G., Bojahr, H., Bolz, O., Coarasa, T., Contreras, J. L., Cortina, J., Denninghoff, S., Fonseca, M. V., Girma, M., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Jung, I., Kankanyan, R., Kestel, M., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Lampeitl, H., Lopez, M., Lorenz, E., Lucarelli, F., Mang, O., Meyer, H., Mirzoyan, R., Moralejo, A., Ona-Wilhelmi, E., Panter, M., Plyasheshnikov, A., Pühlhofer, G., Reyes, R. de los, Rhode, W., Ripken, J., Robrade, J., Rowell, G., Sahakian, V., Samorski, M., Schilling, M., Siems, M., Sobzynska, D., Stamm, W., Tluczykont, M., Vitale, V., Völk, H. J., Wiedner, C. A., Wittek, W., Aharonian, F., Akhperjanian, A., Beilicke, M., Bernlöhr, K., Börst, H.-G., Bojahr, H., Bolz, O., Coarasa, T., Contreras, J. L., Cortina, J., Denninghoff, S., Fonseca, M. V., Girma, M., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Jung, I., Kankanyan, R., Kestel, M., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Lampeitl, H., Lopez, M., Lorenz, E., Lucarelli, F., Mang, O., Meyer, H., Mirzoyan, R., Moralejo, A., Ona-Wilhelmi, E., Panter, M., Plyasheshnikov, A., Pühlhofer, G., Reyes, R. de los, Rhode, W., Ripken, J., Robrade, J., Rowell, G., Sahakian, V., Samorski, M., Schilling, M., Siems, M., Sobzynska, D., Stamm, W., Tluczykont, M., Vitale, V., Völk, H. J., Wiedner, C. A., and Wittek, W.

Abstract

TeV γ-rays from the BL Lac object 1ES 1959+650  have been measured during the years 2000 and 2001 with a significance of 5.2 σat a value of 5.3% of the Crab flux and in May 2002 during strong outbursts with >$23\,\sigma$at a flux level of up to 2.2 Crab, making 1ES 1959+650  the TeV Blazar with the third best event statistics. The deep observation of 197.4 h has been performed with the HEGRA stereoscopic system of 5 imaging atmospheric Cherenkov telescopes (IACT system). 1ES 1959+650  is located at a redshift of $z = 0.047$, providing an intermediate distance between the nearby Blazars Mkn 421 and Mkn 501, and the much more distant object H1426+428. This makes 1ES 1959+650  an important member of the class of TeV Blazars in view of the absorption of TeV photons by the diffuse extragalactic background radiation (DEBRA). The differential energy spectrum of 1ES 1959+650  during the flares can be fitted by a power law with a spectral index of $2.83 \pm 0.14_{\mbox{\tiny stat}} \pm 0.08_{\mbox{\tiny sys}}$or by a power law with an exponential cut-off at $(4.2^{+0.8}_{-0.6~{\mbox{\tiny stat}}} \pm 0.9_{\mbox{\tiny sys}})$TeV and a spectral index of $1.83 \pm 0.15_{\mbox{\tiny stat}} \pm 0.08_{\mbox{\tiny sys}}$. The low state differential energy spectrum obtained with lower statistics can be described by a pure power law with a spectral index of $3.18 \pm 0.17_{\mbox{\tiny stat}} \pm 0.08_{\mbox{\tiny sys}}$.

Published
2003
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28. A search for TeV gamma-ray emission from SNRs, pulsars and unidentified GeV sources in the Galactic plane in the longitude range between $-2^\circ$and $85^\circ$

Author

Aharonian, F. A., Akhperjanian, A. G., Beilicke, M., Bernlöhr, K., Bojahr, H., Bolz, O., Börst, H., Coarasa, T., Contreras, J. L., Cortina, J., Denninghoff, S., Fonseca, V., Girma, M., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Jung, I., Kankanyan, R., Kestel, M., Kettler, J., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Krawczynski, H., Lampeitl, H., Lopez, M., Lorenz, E., Lucarelli, F., Mang, O., Meyer, H., Mirzoyan, R., Moralejo, A., Ona, E., Panter, M., Plyasheshnikov, A., Pühlhofer, G., Rauterberg, G., Reyes, R., Rhode, W., Ripken, J., Röhring, A., Rowell, G. P., Sahakian, V., Samorski, M., Schilling, M., Siems, M., Sobzynska, D., Stamm, W., Tluczykont, M., Völk, H. J., Wiedner, C. A., Wittek, W., Aharonian, F. A., Akhperjanian, A. G., Beilicke, M., Bernlöhr, K., Bojahr, H., Bolz, O., Börst, H., Coarasa, T., Contreras, J. L., Cortina, J., Denninghoff, S., Fonseca, V., Girma, M., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Jung, I., Kankanyan, R., Kestel, M., Kettler, J., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Krawczynski, H., Lampeitl, H., Lopez, M., Lorenz, E., Lucarelli, F., Mang, O., Meyer, H., Mirzoyan, R., Moralejo, A., Ona, E., Panter, M., Plyasheshnikov, A., Pühlhofer, G., Rauterberg, G., Reyes, R., Rhode, W., Ripken, J., Röhring, A., Rowell, G. P., Sahakian, V., Samorski, M., Schilling, M., Siems, M., Sobzynska, D., Stamm, W., Tluczykont, M., Völk, H. J., Wiedner, C. A., and Wittek, W.

Abstract

Using the HEGRA system of imaging atmospheric Cherenkov telescopes, one quarter of the Galactic plane ($-2^\circ < l < 85^\circ$) was surveyed for TeV gamma-ray emission from point sources and moderately extended sources (Ø$\;\le0.8^\circ$). The region covered includes 86 known pulsars (PSR), 63 known supernova remnants (SNR) and nine GeV sources, representing a significant fraction of the known populations. No evidence for emission of TeV gamma radiation was detected, and upper limits range from 0.15 Crab units up to several Crab units, depending on the observation time and zenith angles covered. The ensemble sums over selected SNR and pulsar subsamples and over the GeV-sources yield no indication of emission from these potential sources. The upper limit for the SNR population is 6.7% of the Crab flux and for the pulsar ensemble is 3.6% of the Crab flux.

Published
2002
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29. Variations of the TeV energy spectrum at different flux levels of Mkn 421observed with the HEGRA system of Cherenkov telescopes

Author

Aharonian, F., Akhperjanian, A., Beilicke, M., Bernlöhr, K., Börst, H., Bojahr, H., Bolz, O., Coarasa, T., Contreras, J., Cortina, J., Costamante, L., Denninghoff, S., Fonseca, V., Girma, M., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Jung, I., Kankanyan, R., Kestel, M., Kettler, J., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Krawczynski, H., Lampeitl, H., Lopez, M., Lorenz, E., Lucarelli, F., Mang, O., Meyer, H., Mirzoyan, R., Milite, M., Moralejo, A., Ona, E., Panter, M., Plyasheshnikov, A., Pühlhofer, G., Rauterberg, G., Reyes, R., Rhode, W., Ripken, J., Rowell, G., Sahakian, V., Samorski, M., Schilling, M., Siems, M., Sobzynska, D., Stamm, W., Tluczykont, M., Völk, H. J., Wiedner, C. A., Wittek, W., Remillard, R. A., Aharonian, F., Akhperjanian, A., Beilicke, M., Bernlöhr, K., Börst, H., Bojahr, H., Bolz, O., Coarasa, T., Contreras, J., Cortina, J., Costamante, L., Denninghoff, S., Fonseca, V., Girma, M., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Jung, I., Kankanyan, R., Kestel, M., Kettler, J., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Krawczynski, H., Lampeitl, H., Lopez, M., Lorenz, E., Lucarelli, F., Mang, O., Meyer, H., Mirzoyan, R., Milite, M., Moralejo, A., Ona, E., Panter, M., Plyasheshnikov, A., Pühlhofer, G., Rauterberg, G., Reyes, R., Rhode, W., Ripken, J., Rowell, G., Sahakian, V., Samorski, M., Schilling, M., Siems, M., Sobzynska, D., Stamm, W., Tluczykont, M., Völk, H. J., Wiedner, C. A., Wittek, W., and Remillard, R. A.

Abstract

The nearby BL Lacertae (BL Lac) object Markarian 421 (Mkn 421) at a red shift $z=0.031$was observed to undergo strong TeV γ-ray outbursts in the observational periods from December 1999 until May 2001. The time averaged flux level $F(E>1{\rm \,TeV})$in the 1999/2000 season was $(1.43\pm0.04)$$\times$10-11ph cm-2s-1, whereas in the 2000/2001 season the average integral flux increased to $(4.19\pm0.04)$$\times$10-11ph cm-2s-1. Both energy spectra are curved and well fit by a power law with an exponential cut-off energy at $3.6(+0.4-0.3)_{\rm stat}(+0.9-0.8)_{\rm sys}$TeV. The respective energy spectra averaged over each of the two time periods indicate a spectral hardening for the 2000/2001 spectrum. The photon index changes from $2.39\pm0.09_{\rm stat}$for 1999/2000 to $2.19\pm0.02_{\rm stat}$in 2000/2001. The energy spectra derived for different average flux levels ranging from 0.5 to 10 $\times$10-11ph cm-2s-1follow a clear correlation of photon index and flux level. Generally, the energy spectra are harder for high flux levels. From January to April 2001 Mkn 421showed rapid variability (doubling time as short as 20 min), accompanied with a spectral hardening with increasing flux level within individual nights. For two successive nights (MJD 51989-51991, March 21-23, 2001), this correlation of spectral hardness and change in flux has been observed within a few hours. The cut-off energy for the Mkn 421TeV spectrum remains within the errors constant for the different flux levels and differs by $\Delta E=2.6\pm0.6_{\rm stat}\pm0.6_{\rm sys}$TeV  from the value determined for Mkn 501. This indicates that the observed exponential cut-off in the energy spectrum of Mkn 421is not solely caused by absorption of multi-TeV photons by pair-production processes with photons of the extragalactic near/mid infrared background radiation.

Published
2002
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30. An unidentified TeV source in the vicinity of Cygnus OB2

Author

Aharonian, F., Akhperjanian, A., Beilicke, M., Bernlöhr, K., Börst, H., Bojahr, H., Bolz, O., Coarasa, T., Contreras, J., Cortina, J., Denninghoff, S., Fonseca, V., Girma, M., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Jung, I., Kankanyan, R., Kestel, M., Kettler, J., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Krawczynski, H., Lampeitl, H., Lopez, M., Lorenz, E., Lucarelli, F., Magnussen, N., Mang, O., Meyer, H., Milite, M., Mirzoyan, R., Moralejo, A., Ona, E., Panter, M., Plyasheshnikov, A., Prahl, J., Pühlhofer, G., Rauterberg, G., Reyes, R., Rhode, W., Ripken, J., Röhring, A., Rowell, G. P., Sahakian, V., Samorski, M., Schilling, M., Schröder, F., Siems, M., Sobzynska, D., Stamm, W., Tluczykont, M., Völk, H. J., Wiedner, C. A., Uchiyama, Y., Takahashi, T., Aharonian, F., Akhperjanian, A., Beilicke, M., Bernlöhr, K., Börst, H., Bojahr, H., Bolz, O., Coarasa, T., Contreras, J., Cortina, J., Denninghoff, S., Fonseca, V., Girma, M., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Jung, I., Kankanyan, R., Kestel, M., Kettler, J., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Krawczynski, H., Lampeitl, H., Lopez, M., Lorenz, E., Lucarelli, F., Magnussen, N., Mang, O., Meyer, H., Milite, M., Mirzoyan, R., Moralejo, A., Ona, E., Panter, M., Plyasheshnikov, A., Prahl, J., Pühlhofer, G., Rauterberg, G., Reyes, R., Rhode, W., Ripken, J., Röhring, A., Rowell, G. P., Sahakian, V., Samorski, M., Schilling, M., Schröder, F., Siems, M., Sobzynska, D., Stamm, W., Tluczykont, M., Völk, H. J., Wiedner, C. A., Uchiyama, Y., and Takahashi, T.

Abstract

Deep observation (~113 hrs) of the Cygnus region at TeV energies using the HEGRA stereoscopic system of air Čerenkov telescopes has serendipitously revealed a signal positionally inside the core of the OB association Cygnus OB2, at the edge of the 95% error circle of the EGRET source 3EG J2033+4118, and ~$0.5^\circ$north of Cyg X-3. The source centre of gravity is RA $\alpha_{\rm J2000}$: $20^{\rm hr} 32^{\rm m} 07^{\rm s}\pm 9.2^{\rm s}_{\rm stat} \pm2.2^{\rm s}_{\rm sys}$, Dec $\delta_{\rm J2000}$: $+41^\circ 30^\prime 30^{\prime\prime}\pm 2.0^\prime_{\rm stat} \pm 0.4^\prime_{\rm sys}$. The source is steady, has a post-trial significance of +4.6σ, indication for extension with radius $5.6^\prime$at the ~$3\sigma$level, and has a differential power-law flux with hard photon index of $-1.9 \pm0.3_{\rm stat}\pm0.3_{\rm sys}$. The integral flux above 1 TeV amounts ~3% that of the Crab. No counterpart for the TeV source at other wavelengths is presently identified, and its extension would disfavour an exclusive pulsar or AGN origin. If associated with Cygnus OB2, this dense concentration of young, massive stars provides an environment conducive to particle acceleration and likely subsequent interaction with a nearby gas cloud. Alternatively, one could envisage γ-ray production via a jet-driven termination shock.

Published
2002
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31. A search for gamma-ray emission from the Galactic plane in the longitude range between $\mathsf{37}^\circ$and $\mathsf{43}^\circ$

Author

Aharonian, F. A., Akhperjanian, A. G., Barrio, J. A., Bernlöhr, K., Bolz, O., Börst, H., Bojahr, H., Contreras, J. L., Cortina, J., Denninghoff, S., Fonseca, V., Gonzalez, J. C., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Ibarra, A., Iserlohe, C., Jung, I., Kankanyan, R., Kestel, M., Kettler, J., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Krawczynski, H., Lampeitl, H., Lorenz, E., Lucarelli, F., Magnussen, N., Mang, O., Meyer, H., Mirzoyan, R., Moralejo, A., Padilla, L., Panter, M., Plaga, R., Plyasheshnikov, A., Prahl, J., Pühlhofer, G., Rhode, W., Röhring, A., Rowell, G. P., Sahakian, V., Samorski, M., Schilling, M., Schröder, F., Siems, M., Stamm, W., Tluczykont, M., Völk, H. J., Wiedner, C. A., Wittek, W., Aharonian, F. A., Akhperjanian, A. G., Barrio, J. A., Bernlöhr, K., Bolz, O., Börst, H., Bojahr, H., Contreras, J. L., Cortina, J., Denninghoff, S., Fonseca, V., Gonzalez, J. C., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Ibarra, A., Iserlohe, C., Jung, I., Kankanyan, R., Kestel, M., Kettler, J., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Krawczynski, H., Lampeitl, H., Lorenz, E., Lucarelli, F., Magnussen, N., Mang, O., Meyer, H., Mirzoyan, R., Moralejo, A., Padilla, L., Panter, M., Plaga, R., Plyasheshnikov, A., Prahl, J., Pühlhofer, G., Rhode, W., Röhring, A., Rowell, G. P., Sahakian, V., Samorski, M., Schilling, M., Schröder, F., Siems, M., Stamm, W., Tluczykont, M., Völk, H. J., Wiedner, C. A., and Wittek, W.

Abstract

Using the HEGRA system of imaging atmospheric Cherenkov telescopes, a region of the Galactic plane ($-10^\circ < b < 5^\circ$, $38^\circ < l < 43^\circ$) was surveyed for TeV gamma-ray emission, both from point sources and of diffuse nature. The region covered includes 15 known pulsars, 6 known supernova remnants (SNR) and one unidentified EGRET source. No evidence for emission from point sources was detected; upper limits are typically below 0.1 Crab units for the flux above 1 TeV. For the diffuse gamma-ray flux from the Galactic plane, an upper limit of $6.1\times10^{-15}$ph cm-2s-1sr-1MeV-1was derived under the assumption that the spatial distribution measured by the EGRET instrument extends to the TeV regime. This upper flux limit is a factor of about 1.5 larger than the flux expected from the ensemble of gamma-ray unresolved Galactic cosmic ray sources.

Published
2001
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32. Rejection of the Hypothesis That Markarian 501 T[CLC]e[/CLC]V Photons Are Pure Bose-Einstein Condensates

Author

Aharonian, F., primary, Akhperjanian, A., additional, Barrio, J., additional, Bernlöhr, K., additional, Börst, H., additional, Bojahr, H., additional, Bolz, O., additional, Contreras, J., additional, Cortina, J., additional, Denninghoff, S., additional, Fonseca, V., additional, Gonzalez, J., additional, Götting, N., additional, Heinzelmann, G., additional, Hermann, G., additional, Heusler, A., additional, Hofmann, W., additional, Horns, D., additional, Ibarra, A., additional, Iserlohe, C., additional, Jung, I., additional, Kankanyan, R., additional, Kestel, M., additional, Kettler, J., additional, Kohnle, A., additional, Konopelko, A., additional, Kornmeyer, H., additional, Kranich, D., additional, Krawczynski, H., additional, Lampeitl, H., additional, Lorenz, E., additional, Lucarelli, F., additional, Magnussen, N., additional, Mang, O., additional, Meyer, H., additional, Mirzoyan, R., additional, Moralejo, A., additional, Padilla, L., additional, Panter, M., additional, Plaga, R., additional, Plyasheshnikov, A., additional, Prahl, J., additional, Pühlhofer, G., additional, Röhring, A., additional, Rhode, W., additional, Rowell, G., additional, Sahakian, V., additional, Samorski, M., additional, Schilling, M., additional, Schröder, F., additional, Siems, M., additional, Stamm, W., additional, Tluczykont, M., additional, Völk, H. J., additional, Wiedner, C. A., additional, and Wittek, W., additional

Published
2000
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33. THE TIMING SYSTEM OF THE MAGIC TELESCOPE.

Author

Lucarelli, F., López, M., Oña-Wilhelmi, E., Fonseca, M. V., and Börst, H. G.

Subjects
TELESCOPES, GAMMA rays, ELECTROMAGNETISM, PULSARS, PHOTONS, RADIATION sources
Abstract

The Major Atmospheric Gamma-ray Imaging Čerenkov Telescope (MAGIC) will be the first ground-based Čerenkov telescope able to detect photons with E > 30 GeV. This region of the electromagnetic spectrum, yet unexplored, is fundamental for pulsar physics since theoretical models foreseen a cut-off in the pulsed emission at tens of GeV. In order to perform timing analysis of pulsars, accuracy below milliseconds in the time stamp of the detected event is needed. In this work, we present the timing system of the MAGIC telescope and the first timing analysis performed on real data. [ABSTRACT FROM AUTHOR]

Published
2005

37. A search for gamma-ray emission from the Galactic plane in the longitude range between 37° and 43°

Author

Aharonian, F. A., Akhperjanian, A. G., Barrio, J. A., Bernlöhr, K., Bolz, O., Börst, H., Bojahr, H., Contreras, J. L., Juan Cortina, Denninghoff, S., Fonseca, V., Gonzalez, J. C., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Ibarra, A., Iserlohe, C., Jung, I., Kankanyan, R., Kestel, M., Kettler, J., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Krawczynski, H., Lampeitl, H., Lorenz, E., Lucarelli, F., Magnussen, N., Mang, O., Meyer, H., Mirzoyan, R., Moralejo, A., Padilla, L., Panter, M., Plaga, R., Plyasheshnikov, A., Prahl, J., Pühlhofer, G., Rhode, W., Röhring, A., Rowell, G. P., Sahakian, V., Samorski, M., Schilling, M., Schröder, F., Siems, M., Stamm, W., Tluczykont, M., Völk, H. J., Wiedner, C. A., and Wittek, W.

38. Is the giant radio galaxy M 87 a TeV gamma-ray emitter?

Author

Aharonian, F., Akhperjanian, A., Beilicke, M., Bernlöhr, K., Börst, H. -G, Bojahr, H., Bolz, O., Coarasa, T., Contreras, J. L., Juan Cortina, Denninghoff, S., Fonseca, M. V., Girma, M., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Jung, I., Kankanyan, R., Kestel, M., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Lampeitl, H., Lopez, M., Lorenz, E., Lucarelli, F., Mang, O., Meyer, H., Mirzoyan, R., Moralejo, A., Ona-Wilhelmi, E., Panter, M., Plyasheshnikov, A., Pühlhofer, G., Los Reyes, R., Rhode, W., Ripken, J., Rowell, G., Sahakian, V., Samorski, M., Schilling, M., Siems, M., Sobzynska, D., Stamm, W., Tluczykont, M., Vitale, V., Völk, H. J., Wiedner, C. A., and Wittek, W.

39. Search for TeV gamma ray emission from the Andromeda galaxy

Author

Aharonian, F. A., Akhperjanian, A. G., Beilicke, M., Bernlöhr, K., Bojahr, H., Bolz, O., Börst, H., Coarasa, T., Contreras, J. L., Cortina, J., Denninghoff, S., Fonseca, V., Girma, M., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Jung, I., Kankanyan, R., Kestel, M., Kettler, J., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Krawczynski, H., Lampeitl, H., Lopez, M., Lorenz, E., Lucarelli, F., Mang, O., Meyer, H., Mirzoyan, R., Moralejo, A., Ona, E., Panter, M., Plyasheshnikov, A., Pühlhofer, G., Rauterberg, G., Reyes, R., Rhode, W., Ripken, J., Röhring, A., Gavin Rowell, Sahakian, V., Samorski, M., Schilling, M., Siems, M., Sobzynska, D., Stamm, W., Tluczykont, M., Völk, H. J., Wiedner, C. A., and Wittek, W.

Subjects
Physics, Range (particle radiation), Annihilation, Andromeda Galaxy, Astrophysics::High Energy Astrophysical Phenomena, Dark matter, Astrophysics (astro-ph), Gamma ray, Flux, HEGRA, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Space and Planetary Science, Cherenkov radiation, Astrophysics::Galaxy Astrophysics
Abstract

Using the HEGRA system of imaging atmospheric Cherenkov telescopes, the Andromeda galaxy (M31) was surveyed for TeV gamma ray emission. Given the large field of view of the HEGRA telescopes, three pointings were sufficient to cover all of M31, including also M32 and NGC205. No indications for point sources of TeV gamma rays were found. Upper limits are given at a level of a few percent of the Crab flux. A specific search for monoenergetic gamma-ray lines from annihilation of supersymmetric dark matter particles accumulating near the center of M31 resulted in flux limits in the 10^-13/cm^2s range, well above the predicted MSSM flux levels except for models with pronounced dark-matter spikes or strongly enhanced annihilation rates., Comment: Latex, 7 pages, 4 Figures, submitted to A&A

40. Search for point sources of gamma radiation above 15 TeV with the HEGRA AIROBICC array

Author

Aharonian, F., Akhperjanian, A., Barrio, J. A., Bernlöhr, K., Börst, H., Bojahr, H., Bolz, O., Contreras, J. L., Cortina, J., Denninghoff, S., Fonseca, V., Gebauer, H. J., González, J., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Jung, I., Kankanyan, R., Kestel, M., Kettler, J., Kohnle, A., Konopelko, A., Kornmayer, H., Kranich, D., Krawczynski, H., Lampeitl, H., López, M., Lorenz, E., Lucarelli, F., Magnussen, N., Mang, O., Meyer, H., Mirzoyan, R., Moralejo, A., Oña, E., Padilla, L., Panter, M., Plaga, R., Plyasheshnikov, A., Prahl, J., Pühlhofer, G., Rauterberg, G., Röhring, A., Rhode, W., Gavin Rowell, Sahakian, V., Samorski, M., Schilling, M., Schmele, D., Schröder, F., Sevilla, I., Siems, M., Stamm, W., Tluczykont, M., Völk, H. J., Wiedner, C. A., and Wittek, W.

41. TeV gamma rays from the blazar H 1426+428 and the diffuse extragalactic background radiation

Author

Aharonian, F., Akhperjanian, A., Barrio, J., Beilicke, M., Bernlöhr, K., Börst, H., Bojahr, H., Bolz, O., Contreras, J., Cornils, R., Cortina, J., Denninghoff, S., Fonseca, V., Girma, M., Gonzalez, J., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Jung, I., Kankanyan, R., Kestel, M., Kettler, J., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Krawczynski, H., Lampeitl, H., Lopez, M., Lorenz, E., Fabrizio Lucarelli, Magnussen, N., Mang, O., Meyer, H., Mirzoyan, R., Moralejo, A., Ona, E., Padilla, L., Panter, M., Plaga, R., Plyasheshnikov, A., Pühlhofer, G., Rauterberg, G., Röhring, A., Rhode, W., Robrade, J., Rowell, G., Sahakian, V., Samorski, M., Schilling, M., Schröder, F., Sevilla, I., Siems, M., Stamm, W., Tluczykont, M., Völk, H. J., Wiedner, C. A., and Wittek, W.

42. Observations of H1426+428 with HEGRA observations in 2002 and reanalysis of 1999&2000 data

Author

Aharonian, F., Akhperjanian, A., Beilicke, M., Bernlöhr, K., Börst, H. -G, Bojahr, H., Bolz, O., Coarasa, T., Contreras, J. L., Cortina, J., Costamante, L., Denninghoff, S., Fonseca, M. V., Girma, M., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Jung, I., Kankanyan, R., Kestel, M., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Lampeitl, H., Lopez, M., Lorenz, E., Lucarelli, F., Mang, O., Mazine, D., Meyer, H., Mirzoyan, R., Moralejo, A., Ona-Wilhelmi, E., Panter, M., Plyasheshnikov, A., Prahl, J., Pühlhofer, G., Los Reyes, R., Rhode, W., Ripken, J., Rowell, G., Sahakian, V., Samorski, M., Schilling, M., Siems, M., Sobzynska, D., Stamm, W., Tluczykont, M., Vitale, V., Völk, H. J., Wiedner, C. A., and Wittek, W.

43. Optimizing the angular resolution of the HEGRA telescope system to study the emission region of VHE gamma rays in the Crab Nebula

Author

Aharonian, F. A., Akhperjanian, A. G., Barrio, J. A., Bernlöhr, K., Bojahr, H., Bolz, O., Börst, H., Contreras, J. L., Cortina, J., Denninghoff, S., Fonseca, V., Gonzalez, J. C., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Ibarra, A., Iserlohe, C., Jung, I., Kankanyan, R., Kestel, M., Kettler, J., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Krawczynski, H., Lampeitl, H., Lorenz, E., Lucarelli, F., Magnussen, N., Mang, O., Meyer, H., Mirzoyan, R., Moralejo, A., Luis Padilla, Panter, M., Plaga, R., Plyasheshnikov, A., Prahl, J., Pühlhofer, G., Rhode, W., Röhring, A., Rowell, G., Sahakian, V., Samorski, M., Schilling, M., Schröder, F., Siems, M., Stamm, W., Tluczykont, M., Völk, H. J., Wiedner, C., and Wittek, W.

44. Search for a TeV gamma-ray halo of Mkn 501

Author

Aharonian, F. A., Akhperjanian, A. G., Barrio, J. A., Bernlöhr, K., Bolz, O., Börst, H., Bojahr, H., Contreras, J. L., Cortina, J., Denninghoff, S., Fonseca, V., Gonzalez, J. C., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Ibarra, A., Iserlohe, C., Jung, I., Kankanyan, R., Kestel, M., Ketter, J., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Krawczynski, H., Lampeitl, H., Lorenz, E., Fabrizio Lucarelli, Magnussen, N., Mang, O., Meyer, H., Mirzoyan, R., Moralejo, A., Padilla, L., Panter, M., Plaga, R., Plyasheshnikov, A., Prahl, J., Pühlhofer, G., Rhode, W., Röhring, A., Rowell, G. P., Sahakian, V., Samorski, M., Schilling, M., Schröder, F., Siems, M., Stamm, W., Tluczykont, M., Völk, H. J., Wiedner, C., and Wittek, W.

45. J Musculoskelet Neuronal Interact

Author

Dl, Belavý, Bock O, Börst H, Armbrecht G, Gast U, Degner C, Beller G, Soll H, Salanova M, Habazettl H, Heer M, de Haan A, Df, Stegeman, Cerretelli P, Blottner D, Joern Rittweger, Gelfi C, Kornak U, Felsenberg D, Kinesiology, Research Institute MOVE, Molecular cell biology and Immunology, and MOVE Research Institute

Subjects
Adult, Male, Spaceflight, Middle Aged, Vibration, Exercise Therapy, Berlin, Young Adult, Countermeasures, Treatment Outcome, Physical Fitness, Humans, Osteoporosis, Microgravity, Inactivity, Exercise, Functional Neurogenomics [DCN 2], Bed Rest, Weightlessness Simulation, Weltraumphysiologie
Abstract

Contains fulltext : 89007.pdf (Publisher’s version ) (Open Access) Long-term bed-rest is used to simulate the effect of spaceflight on the human body and test different kinds of countermeasures. The 2nd Berlin BedRest Study (BBR2-2) tested the efficacy of whole-body vibration in addition to high-load resisitance exercise in preventing bone loss during bed-rest. Here we present the protocol of the study and discuss its implementation. Twenty-four male subjects underwent 60-days of six-degree head down tilt bed-rest and were randomised to an inactive control group (CTR), a high-load resistive exercise group (RE) or a high-load resistive exercise with whole-body vibration group (RVE). Subsequent to events in the course of the study (e.g. subject withdrawal), 9 subjects participated in the CTR-group, 7 in the RVE-group and 8 (7 beyond bed-rest day-30) in the RE-group. Fluid intake, urine output and axiallary temperature increased during bed-rest (p < .0001), though similarly in all groups (p > or = .17). Body weight changes differed between groups (p < .0001) with decreases in the CTR-group, marginal decreases in the RE-group and the RVE-group displaying significant decreases in body-weight beyond bed-rest day-51 only. In light of events and experiences of the current study, recommendations on various aspects of bed-rest methodology are also discussed. 01 september 2010

46. A search for TeV gamma-ray emission from SNRs, pulsars and unidentified GeV sources in the galactic plane in the longitude range between -2° and 85°

Author

Aharonian, F. A., Akhperjanian, A. G., Beilicke, M., Bernlöhr, K., Bojahr, H., Bolz, O., Börst, H., Coarasa, T., Contreras, J. L., Juan Cortina, Denninghoff, S., Fonseca, V., Girma, M., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Jung, I., Kankanyan, R., Kestel, M., Kettler, J., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Krawczynski, H., Lampeitl, H., Lopez, M., Lorenz, E., Lucarelli, F., Mang, O., Meyer, H., Mirzoyan, R., Moralejo, A., Ona, E., Panter, M., Plyasheshnikov, A., Pühlhofer, G., Rauterberg, G., Reyes, R., Rhode, W., Ripken, J., Röhring, A., Rowell, G. P., Sahakian, V., Samorski, M., Schilling, M., Siems, M., Sobzynska, D., Stamm, W., Tluczykont, M., Völk, H. J., Wiedner, C. A., and Wittek, W.

47. Detection of TeV gamma-rays from the BL Lac 1ES 1959+650 in its low states and during a major outburst in 2002

Author

Aharonian, F., Akhperjanian, A., Beilicke, M., Bernlöhr, K., Börst, H. -G, Bojahr, H., Bolz, O., Coarasa, T., Contreras, J. L., Juan Cortina, Denninghoff, S., Fonseca, M. V., Girma, M., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Jung, I., Kankanyan, R., Kestel, M., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Lampeitl, H., Lopez, M., Lorenz, E., Lucarelli, F., Mang, O., Meyer, H., Mirzoyan, R., Moralejo, A., Ona-Wilhelmi, E., Panter, M., Plyasheshnikov, A., Pühlhofer, G., Los Reyes, R., Rhode, W., Ripken, J., Robrade, J., Rowell, G., Sahakian, V., Samorski, M., Schilling, M., Siems, M., Sobzynska, D., Stamm, W., Tluczykont, M., Vitale, V., Völk, H. J., Wiedner, C. A., and Wittek, W.

48. Reanalysis of the high energy cutoff of the 1997 Mkn 501 TeV energy spectrum

Author

Aharonian, F. A., Akhperjanian, A. G., Barrio, J. A., Bernlöhr, K., Bolz, O., Börst, H., Bojahr, H., Contreras, J. L., Cortina, J., Denninghoff, S., Fonseca, V., Gonzalez, J. C., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Ibarra, A., Iserlohe, C., Jung, I., Kankanyan, R., Kestel, M., Kettler, J., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Krawczynski, H., Lampeitl, H., Lorenz, E., Lucarelli, F., Magnussen, N., Mang, O., Meyer, H., Mirzoyan, R., Moralejo, A., Padilla, L., Panter, M., Plaga, R., Plyasheshnikov, A., Prahl, J., Pühlhofer, G., Rhode, W., Röhring, A., Gavin Rowell, Sahakian, V., Samorski, M., Schilling, M., Schröder, F., Siems, M., Stamm, W., Tluczykont, M., Völk, H. J., Wiedner, C., and Wittek, W.

49. A study of Tycho's SNR at TeV energies with the HEGRA CT-system

Author

Aharonian, F. A., Akhperjanian, A. G., Barrio, J. A., Bernlöhr, K., Börst, H., Bojahr, H., Bolz, O., Contreras, J. L., Cortina, J., Denninghoff, S., Fonseca, V., Gonzalez, J. C., Götting, N., Heinzelmann, G., Hermann, G., Heusler, A., Hofmann, W., Horns, D., Ibarra, A., Jung, I., Kankanyan, R., Kestel, M., Kettler, J., Kohnle, A., Konopelko, A., Kornmeyer, H., Kranich, D., Krawczynski, H., Lampeitl, H., Lorenz, E., Fabrizio Lucarelli, Magnussen, N., Mang, O., Meyer, H., Mirzoyan, R., Moralejo, A., Padilla, L., Panter, M., Plaga, R., Plyasheshnikov, A., Prahl, J., Pühlhofer, G., Rauterberg, G., Röhring, A., Rhode, W., Rowell, G. P., Sahakian, V., Samorski, M., Schilling, M., Schröder, F., Stamm, W., Tluczykont, M., Völk, H. J., Wiedner, C., and Wittek, W.

Subjects
Physics, Photon, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics (astro-ph), Hadron, FOS: Physical sciences, HEGRA, Flux, Astronomy and Astrophysics, Astrophysics, law.invention, Telescope, Space and Planetary Science, law, Limit (mathematics), Supernova remnant, Astrophysics::Galaxy Astrophysics, Cherenkov radiation
Abstract

Tycho's supernova remnant (SNR) was observed during 1997 and 1998 with the HEGRA Cherenkov Telescope System in a search for gamma-ray emission at energies above ~1 TeV. An analysis of these data, ~65 hours in total, resulted in no evidence for TeV gamma-ray emission. The 3sigma upper limit to the gamma-ray flux (>1 TeV) from Tycho is estimated at 5.78x10^{-13} photons cm^{-2} s^{-1}, or 33 milli-Crab. We interpret our upper limit within the framework of the following scenarios: (1) that the observed hard X-ray tail is due to synchrotron emission. A lower limit on the magnetic field within Tycho may be estimated B>=22 microG, assuming that the RXTE-detected X-rays were due to synchrotron emission. However, using results from a detailed model of the ASCA emission, a more conservative lower limit B>=6 microG is derived. (2) the hadronic model of Drury, Aharonian & Voelk, and (3) the more recent time-dependent kinetic theory of Berezhko & Voelk. Our upper limit lies within the range of predicted values of both hadronic models, according to uncertainties in physical parameters of Tycho, and shock acceleration details. In the latter case, the model was scaled to suit the parameters of Tycho and re-normalised to account for a simplification of the original model. We find that we cannot rule out Tycho as a potential contributor at an average level to the Galactic cosmic-ray flux., 9 pages, 6 figures. Accepted for publication in Astronomy and Astrophysics

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