920 results on '"Hermsen, W."'
Search Results
102. ORIGIN: Metal Creation and Evolution from the Cosmic Dawn
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Kouveliotou, C, vanderHorst, A, Weisskopf, M, White, N, denHerder, J. W, Costantini, E, denHartog, R, Hermsen, W, in'tZhand, J, Kaastra, J, dePlaa, J, Jonker, P, deKorte, P, Piro, L, Cocchi, M, Colasanti, L, Corsi, A, DeRosa, A, DelSanto, M, DiCosimo, S, Gendre, B, Macculi, C, Natalucci, L, Ubertini, P, and Ohashi, T
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Astrophysics - Abstract
ORIGIN is a proposal for the M3 mission call of ESA aimed at the study of metal creation from the epoch of cosmic dawn. Using high-spectral resolution in the soft X-ray band, ORIGIN will be able to identify the physical conditions of all abundant elements between C and Ni to red-shifts of z=10, and beyond. The mission will answer questions such as: When were the first metals created? How does the cosmic metal content evolve? Where do most of the metals reside in the Universe? What is the role of metals in structure formation and evolution? To reach out to the early Universe ORIGIN will use Gamma-Ray Bursts (GRBs) to study their local environments in their host galaxies. This requires the capability to slew the satellite in less than a minute to the GRB location. By studying the chemical composition and properties of clusters of galaxies we can extend the range of exploration to lower redshifts (z approx. 0.2). For this task we need a high-resolution spectral imaging instrument with a large field of view. Using the same instrument, we can also study the so far only partially detected baryons in the Warm-Hot Intergalactic Medium (WHIM). The less dense part of the WHIM will be studied using absorption lines at low redshift in the spectra for GRBs. The ORIGIN mission includes a Transient Event Detector (coded mask with a sensitivity of 0.4 photon/sq cm/s in 10 s in the 5-150 keV band) to identify and localize 2000 GRBs over a five year mission, of which approx.65 GRBs have a redshift >7. The Cryogenic Imaging Spectrometer, with a spectral resolution of 2.5 eV, a field of view of 30 arcmin and large effective area below 1 keV has the sensitivity to study clusters up to a significant fraction of the virial radius and to map the denser parts of the WHIM (factor 30 higher than achievable with current instruments). The payload is complemented by a Burst InfraRed Telescope to enable onboard red-shift determination of GRBs (hence securing proper follow up of high-z bursts) and also probes the mildly ionized state of the gas. Fast repointing is achieved by a dedicated Controlled Momentum Gyro and a low background is achieved by the selected low Earth orbit.
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- 2012
103. X-ray properties of the mode-switching pulsar PSR B0943+10
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Mereghetti, S, Kuiper, L, Tiengo, A, Hessels, J, Hermsen, W, Stovall, K, Possenti, A, Rankin, J, Esposito, P, Turolla, R, Mitra, D, Wright, G, Stappers, B, Horneffer, A, Oslowski, S, Serylak, M, Griessmeier, J, Rigoselli, M, Mereghetti S., Kuiper L., Tiengo A., Hessels J., Hermsen W., Stovall K., Possenti A., Rankin J., Esposito P., Turolla R., Mitra D., Wright G., Stappers B., Horneffer A., Oslowski S., Serylak M., Griessmeier J. -M., Rigoselli M., Mereghetti, S, Kuiper, L, Tiengo, A, Hessels, J, Hermsen, W, Stovall, K, Possenti, A, Rankin, J, Esposito, P, Turolla, R, Mitra, D, Wright, G, Stappers, B, Horneffer, A, Oslowski, S, Serylak, M, Griessmeier, J, Rigoselli, M, Mereghetti S., Kuiper L., Tiengo A., Hessels J., Hermsen W., Stovall K., Possenti A., Rankin J., Esposito P., Turolla R., Mitra D., Wright G., Stappers B., Horneffer A., Oslowski S., Serylak M., Griessmeier J. -M., and Rigoselli M.
- Abstract
The mode-switching pulsar PSR B0943+10 has been extensively studied in the radio band for many years and, more recently, it has been found to vary also in X-rays, with a flux anticorrelated with the radio emission. Here we review the results of long observations of PSR B0943+10 carried out with XMM-Newton and the LOFAR, LWA and Arecibo radio telescopes in 2014. These results support a scenario in which both unpulsed non-thermal emission, likely of magnetospheric origin, and pulsed thermal emission from a small polar cap (∼1500 m 2 ) with a strong non-dipolar magnetic field (∼ 10 14 G), are present during both radio modes and vary in intensity in a correlated way.
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- 2017
104. X-rays from the mode-switching PSR B0943+10
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Mereghetti, S, Kuiper, L, Tiengo, A, Hessels, J, Hermsen, W, Stovall, K, Possenti, A, Rankin, J, Esposito, P, Turolla, R, Mitra, D, Wright, G, Stappers, B, Horneffer, A, Oslowski, S, Serylak, M, Griessmeier, J, Rigoselli, M, Mereghetti S., Kuiper L., Tiengo A., Hessels J., Hermsen W., Stovall K., Possenti A., Rankin J., Esposito P., Turolla R., Mitra D., Wright G., Stappers B., Horneffer A., Oslowski S., Serylak M., Griessmeier J. -M., Rigoselli M., Mereghetti, S, Kuiper, L, Tiengo, A, Hessels, J, Hermsen, W, Stovall, K, Possenti, A, Rankin, J, Esposito, P, Turolla, R, Mitra, D, Wright, G, Stappers, B, Horneffer, A, Oslowski, S, Serylak, M, Griessmeier, J, Rigoselli, M, Mereghetti S., Kuiper L., Tiengo A., Hessels J., Hermsen W., Stovall K., Possenti A., Rankin J., Esposito P., Turolla R., Mitra D., Wright G., Stappers B., Horneffer A., Oslowski S., Serylak M., Griessmeier J. -M., and Rigoselli M.
- Abstract
New simultaneous X-ray and radio observations of the archetypal mode-switching pulsar PSR B0943+10 have been carried out with XMM-Newton and the LOFAR, LWA and Arecibo radio telescopes in November 2014. They allowed us to better constrain the X-ray spectral and variability properties of this pulsar and to detect, for the first time, the X-ray pulsations also during the X-ray-fainter mode. The combined timing and spectral analysis indicates that unpulsed non-thermal emission, likely of magnetospheric origin, and pulsed thermal emission from a small polar cap are present during both radio modes and vary in a correlated way.
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- 2017
105. Analysis of COMPTEL gamma-ray burst locations and spectra
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Kippen, R. M., Ryan, J., Connors, A., McConnell, M., Winkler, C., Hanlon, L. O., Schönfelder, V., Greiner, J., Varendorff, M., Collmar, W., Hermsen, W., and Kuiper, L.
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- 1995
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106. Comptel analysis of GRB 940217
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Winkler, C., Bennett, K., Hanlon, L. O., O'Flaherty, K. S., Williams, O. R., Kippen, R. M., Ryan, J., Collmar, W., Schönfelder, V., Steinle, H., and Hermsen, W.
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- 1995
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107. Interstellar dust, chirality, comets and the origins of life: Life from dead stars?
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Greenberg, J. Mayo, Kouchi, Akira, Niessen, Wilfried, Irth, Hubertus, van Paradijs, Jan, de Groot, Menno, and Hermsen, W.
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- 1995
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108. Book reviews
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Hermsen, W., Stamm, W., Nieuwenhuijzen, H., Plez, B., Koch-Miramond, L., Schadee, A., De Greve, J. P., Icke, Vincent, Kresák, Ľ., Dekker, E., Bonnet-Bidaud, J. -M., and Foing, B. H.
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- 1994
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109. Chandra and RXTE studies of the X-ray/γ-ray millisecond pulsar PSR J0218+4232
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Kuiper, L., Hermsen, W., and Stappers, B.
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- 2004
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110. A Multi-Wavelength Study of WR140 (HD 193793, WC7+04-5) — A Colliding Wind Binary
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Van Der Hucht, K. A., Williams, P. M., Setia Gunawan, D. Y. A., Wamsteker, W., Pollock, A. M. T., Bouchet, P., Kidger, M. R., Hermsen, W., Spoelstra, T. A. TH., De Bruyn, A. G., Wamsteker, W., editor, Longair, M. S., editor, and Kondo, Y., editor
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- 1994
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111. Book reviews
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Contant, Jean-Michel, Einasto, J., Butcher, H. R., Brinkman, A. C., Langer, N., Hermsen, W., and Ne'eman, Y.
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- 1991
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112. Time Averaged Pulse Phase Resolved Spectra of the Vela Pulsar Measured by Comptel at MeV Energies
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Kuiper, L., primary, Hermsen, W., additional, Schönfelder, V., additional, Bennett, K., additional, and Connors, A., additional
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- 1998
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113. 26Al in the local interstellar medium
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Knödlseder, J., primary, Bennett, K., additional, Bloemen, H., additional, Diehl, R., additional, Hermsen, W., additional, Oberlack, U., additional, Ryan, J., additional, Schönfelder, V., additional, and von Ballmoos, P., additional
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- 1998
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114. 26Al radioactivity in the galaxy
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Diehl, R., primary, Oberlack, U., additional, Knödlseder, J., additional, Bennett, K., additional, Bloemen, H., additional, Hermsen, W., additional, Ryan, J., additional, Schönfelder, V., additional, and von Ballmoos, P., additional
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- 1998
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115. Interstellar Dust, Chirality, Comets and the Origins of Life: Life From Dead Stars?
- Author
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Greenberg, J. Mayo, primary, Kouchi, Akira, additional, Niessen, Wilfried, additional, Irth, Hubertus, additional, van Paradijs, Jan, additional, de Groot, Menno, additional, and Hermsen, W., additional
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- 1995
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116. Emission from44 Ti associated with a previously unknown Galactic supernova
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Iyudin, A. F., Schonfelder, V., Bennett, K., Bloemen, H., Diehl, R., Hermsen, W., Lichti, G. G., van der Meulen, R. D., Ryan, J., and Winkler, C.
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- 1998
117. Gamma Radiation from PSR B1055-52
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Thompson, D. J, Bailes, M, Bertsch, D. L, Cordes, J, DAmico, N, Esposito, J. A, Finley, J, Hartman, R. C, Hermsen, W, Kanbach, G, Kaspi, V. M, Kniffen, D. A, Kuiper, L, Lin, Y. C, Lyne, A, Manchester, R, Matz, S. M, Mayer-Hasselwander, H. A, Michelson, P. F, and Nolan, P. L
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Space Radiation - Abstract
The telescopes on the Compton Gamma Ray Observatory (CGRO) have observed PSR B1055-52 a number of times between 1991 and 1998. From these data, a more detailed picture of the gamma radiation from this source has been developed, showing several characteristics which distinguish this pulsar: the light curve is complex; there is no detectable unpulsed emission; the energy spectrum is flat, with no evidence of a sharp high-energy cutoff up to greater than 4 GeV. Comparisons of the gamma-ray data with observations at longer wavelengths show that no two of the known gamma-ray pulsars have quite the same characteristics; this diversity makes interpretation in terms of theoretical models difficult.
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- 1999
118. Gamma Radiation from PSR B1055-52
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Thompson, D. J, Bailes, M, Bertsch, D. L, Cordes, J, DAmico, N. D, Esposito, J. A, Finley, J, Hartman, R. C, Hermsen, W, Kanbach, G, Kaspi, V. M, Kniffen, D. A, Kuiper, L, Lin, Y. C, Lyne, A, Manchester, R, Matz, S. M, Mayer-Hasselwander, H. A, Michelson, P. F, and Nolan, P. L
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Space Radiation - Abstract
The telescopes on the Compton Gamma Ray Observatory (CCRO) have observed PSR B1055-52 a number of times between 1991 and 1998. From these data, a more detailed picture of the gamma radiation from this source has been developed, showing several characteristics which distinguish this pulsar: the light curve is complex; there is no detectable unpulsed emission; the energy spectrum is flat, with no evidence of a sharp high-energy cutoff up to greater than 4 GeV. Comparisons of the gamma-ray data with observations at longer wavelengths show that no two of the known gamma-ray pulsars have quite the same characteristics; this diversity makes interpretation in terms of theoretical models difficult.
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- 1998
119. Evidence for COMPTEL detections of low-energy gamma rays from HVC complexes
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Blom, J. J, Bloemen, H, Bykov, A. M, Burton, W. B, Hartmann, Dap, Hermsen, W, Iyudin, A. F, Ryan, J, Schoenfelder, V, Strong, A. W, and Uvarov, Yu. A
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Space Radiation - Abstract
Observational evidence of extended MeV emissions that may be associated with high velocity clouds (HVCs) is reported on. Based on observations acquired between 1991 and 1996 with the Compton telescope (COMPTEL), evidence is found for intense gamma ray radiation at 0.75 to 3 MeV from the general direction of two HVC regions. One bright gamma ray excess is located between the HVC complexes M and A, adjacent to the Lockman hole and is seen to approximately cover a sky area of exceptionally low H I column densities. A second source is detected at the high velocity end of complex C near the Draco Nebula. Both gamma ray excesses appear to consist of a time variable source and a diffuse emission component. The enhanced diffuse soft X-rays seen by Rosat from both HVC regions may be closely related to the gamma ray emission in terms of bremsstrahlung arising from HVC interactions with the galactic disk or lower halo.
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- 1997
120. New COMPTEL results on the Orion/Monoceros region
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Bloemen, H, Bykov, A. M, Bozhokin, S. V, Diehl, R, Hermsen, W, vanderMeulen, R. D, Oberlack, U, Ryan, J, Schoenfelder, V, and Strong, A. W
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Astronomy - Abstract
Results from recent observations of the Orion/Monoceros region, acquired with the Compton telescope (COMPTEL), are summarized, confirming previously reported results of excessive 3 to 7 MeV emission which is probably due to nuclear de-excitation lines from C-12 and O-16 nuclei following energetic nuclear interactions. The emphasis is on findings concerning the extent of the emission region. It is found that the emission extends over the entire cloud complex, although it may result from a few localized source regions. A preliminary spectrum is presented which indicates that the emission is widely spread over the 3 to 7 MeV range, suggesting a dominantly broadline origin from energetic C and O nuclei. The spectrum shows features that may be due to the splitting of the C and O lines.
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- 1997
121. New COMPTEL results on pulsar studies at MeV energies
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Hermsen, W, Kuiper, L, Schoenfelder, V, Strong, A. W, Bennett, K, Much, R, McConnell, M, Ryan, J, and Carraminana, A
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Astronomy - Abstract
The Compton telescope (COMPTEL) onboard the Compton Gamma Ray Observatory (CGRO) detected the pulsar PSR B1951-32 at MeV energies, and found indications of a signal from PSR B0656+14. In the combined spectra from COMPTEL and the energetic gamma ray experiment telescope (EGRET) onboard CGRO, it can be seen that the maximum luminosities of these objects are reached in the COMPTEL energy range. These spectra can be compared with those from four other pulsars observed in MeV energies with COMPTEL. The spectral properties of five of the six pulsars, Vela, PSR B1509-58, PSR B1951-32 and PSR B0656+14, require breaks and bends at MeV energies. The sixth pulsar, the Crab pulsar, approximately follows a power law flux relation from keV to GeV energies. It is concluded that this spectral behavior may play a role in the discrimination between current gamma ray emission models.
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- 1997
122. COMPTEL observations of GRO J1655-40
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vanDijk, R, Bennett, K, Winkler, C, Bloemen, H, Hermsen, W, Diehl, R, Schoenfelder, V, McConnell, M, and Ryan, J
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Astronomy - Abstract
The transient black hole candidate GRO J1655-40 was shown elsewhere to eject matter at apparently superluminal velocities. The oriented scintillation spectrometer experiment (OSSE) spectra, measured during the X-ray outbursts, are consistent with a single power law up to 600 keV, with no evidence of a high energy cutoff. The detection of the flaring behavior of this source up to 10 MeV was claimed elsewhere. The Compton telescope (COMPTEL) observations in the 0.75 to 30 MeV band of this source are analyzed. The upper limits on the time averaged emission are presented and gamma ray flares are searched for. It is concluded that the COMPTEL data can neither confirm nor refute the claimed detection of a large gamma ray flare from this source. The gamma ray flare search in five years' worth of data did not reveal evidence for the occurrence of strong flares on timescales of two days.
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- 1997
123. Fingerprints of nucleosynthesis in the local spiral arm
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Knoedlseder, J, Bennett, K, Bloemen, H, Diehl, R, Hermsen, W, Oberlack, U, Ryan, J, Schoenfelder, V, and vonBallmoos, P
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Astrophysics - Abstract
The local spiral arm with its inherent massive star population is a natural site of recent nucleosynthesis activity. The features found in 1.8 MeV observation of candidate Al-26 sources situated in this structure are discussed. The emphasis is on Loop 1, a nearby superbubble which is possibly the site of a recent supernova explosion.
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- 1997
124. The Crab nebula and pulsar in the MeV energy range
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Much, R, Bennett, K, Buccheri, R, Busetta, M, Diehl, R, Forrest, D, Hermsen, W, Kuiper, L, Lichti, G. G, and Mcconnell, M
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Astronomy - Abstract
The imaging Compton Telescope (COMPTEL) is sensitive in the energy range of 0.75 to 30 MeV. COMPTEL observed the Crab several times during the Compton Gamma Ray Observatory (CGRO) sky survey and CGRO Phase II. Both the Crab pulsar and nebula are detected over the entire COMPTEL energy range. The phase-averaged energy spectra of the Crab Pulsar and Nebula are presented. The combined observations provide sufficient statistics for a phase-resolved analysis of the Crab pulsar spectrum.
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- 1995
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125. The search for MeV gamma-ray pulsars with COMPTEL
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Bennett, K, Buccheri, R, Busetta, M, Carraminana, A, Connors, A, Diehl, R, Hermsen, W, Kuiper, L, Lichti, G. G, and Much, R
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Astronomy - Abstract
The Compton Gamma Ray Observatory (CGRO) completed a full sky survey in November 1993 during which the number of known gamma-ray pulsars more than doubled. During this survey the Compton Telescope (COMPTEL) observed the classical isolated pulsars Crab and Vela and detected PSR 1509-58. Attempts to detect the newly discovered pulsars, Geminga, PSR 1706-44 and PSR 1055-52, in the COMPTEL energy range provide only upper limits. The results of these analyses are presented together with the outcome of a search for further candidate radio pulsars whose ephemerides are given in the Princeton Pulsar Catalogue.
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- 1995
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126. CGRO-Comptel observations of the Centaurus A region
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Steinle, H, Bennett, K, Bloemen, H, Collmar, W, Diehl, R, Hermsen, W, Lichti, G, Mcconnell, M, Morris, D, and Much, R
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Astronomy - Abstract
The sky region containing the active radio-galaxy Centaurus A has repeatedly been observed with the (COMPTEL) instrument onboard the Compton Gamma Ray Observatory (CGRO). The nine observation periods during the CGRO phases I and II in which Cen A was in the field of view of COMPTEL are spread over 18 months in the years 1991 to 1993. The energy range 0.75 to 30 MeV is covered. Clear evidence for a source with emission up to several MeV is seen from a region coinciding with the position of Cen A. The spectra change significantly over approximately 6 months between the two observation phases. A possible source confusion with the nearby gamma-ray source MS1312.1-4221 is discussed.
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- 1995
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127. Strong gamma-ray bursts observed by COMPTEL during its second year of operation
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Kippen, R. M, Connors, A, Mcconnell, M, Ryan, J, Collmar, W, Greiner, J, Schonfelder, V, Varendorff, M, Hermsen, W, and Kuiper, L
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Astronomy - Abstract
The imaging Compton telescope (COMPTEL) onboard the Compton Gamma Ray Observatory (CGRO) can localize gamma-ray bursts occurring inside its approximately 1 sr field-of-view in the energy range from 0.75 to 30 MeV with location accuracy of 1 deg. Additional time-resolved spectral measurements in the energy range 0.1 to 10 MeV are made by individual COMPTEL 'burst' detectors. During its second year of operation COMPTEL observed several gamma-ray bursts. Locations of five strong bursts (including the rapidly imaged events GRB 930131 and GRB 930309) are presented here along with the findings from preliminary spectral analysis.
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- 1995
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128. Diffuse continuum gamma rays from the Galaxy observed by COMPTEL
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Strong, A. W, Bennett, K, Bloemen, H, Diehl, R, Hermsen, W, Morris, D, Schonfelder, V, Stacy, J. G, De Vries, C, and Varendorff, M
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Astrophysics - Abstract
The diffuse Galactic continuum gamma-ray emission has been studied using the full Sky Survey from COMPTEL on the Compton Observatory CGRO. The diffuse emission appears to be visible in the whole 0.75-30 MeV range covered by the instrument, although a considerable contribution from unresolved point sources cannot be excluded. A correlation analysis using HI and CO surveys of the Galaxy is used to derive the Galactic emissivity spectrum, and this is consistent with a smooth continuation to the spectrum at higher energies derived by a similar analysis of COS-B data. The apparent conversion factor from integrated CO temperature to molecular hydrogen column density can also be determined from the correlation analysis. The value obtained is consistent with results from COS-B and other non-gamma-ray methods. Calculations of the emissivity spectrum from bremsstrahlung from a cosmic-ray electron spectrum based on propagation models are compared with the observations.
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- 1994
129. COMPTEL observations of the 1.809 MeV gamma-ray line from galactic Al-26
- Author
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Diehl, R, Dpraz, C, Bennett, K, Bloemen, H, Deboer, H, Hermsen, W, Lichti, G. G, Mcconnell, M, Morris, D, and Ryan, J
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Astronomy - Abstract
The COMPTEL experiment on the Compton Gamma-Ray Observatory (CGRO) has been demonstrated to be capable of imaging the Galaxy within its field of view of about 1 steradian in the 1.809 MeV gamma-ray line originating from radioactive Al-26. The combined data from the CGRO sky survey in 1991/1992 have been analyzed to provide a first map of the inner Galaxy in this gamma-ray line. The 1.809 MeV emission appears extended along the inner 70 deg of the Galactic plane, with a relatively sharp falloff outside this regime. Correlations with massive stars and supernova remnants as possible tracers of the candidate Al-26 sources are discussed.
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- 1994
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130. Diffuse galactic continuum emission measured by COMPTEL and the cosmic-ray electron spectrum
- Author
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Strong, A. W, Diehl, R, Schoenfelder, V, Varendorff, M, Youssefi, G, Bloemen, H, Hermsen, W, De Vries, C, Morris, D, and Stacy, J. G
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Astronomy - Abstract
Diffuse galactic continuum gamma-ray emission in the 0.75-30 MeV range from the inner Galaxy has been studied using data from COMPTEL on the Compton Gamma-Ray Observatory. Observations of the inner Galaxy from the Sky Survey have been used. The imaging properties of COMPTEL enable spatial analysis of the gamma-ray distribution using model fitting. A model based on atomic and molecular gas distributions in the Galaxy has been used to derive the emissivity spectrum of the gamma-ray emission and this spectrum is compared with theoretical estimates of bremsstrahlung emission from cosmic-ray electrons.
- Published
- 1994
- Full Text
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131. COMPTEL observations of Ti-44 gamma-ray line emission from Cas A
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Iyudin, A. F, Diehl, R, Bloemen, H, Hermsen, W, Lichti, G. G, Morris, D, Ryan, J, Schoenfelder, V, Steinle, H, and Varendorff, M
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Astronomy - Abstract
The Compton Telescope (COMPTEL) telescope aboard the Compton Gamma-Ray Observatory (CGRO) is capable of imaging gamma-ray line sources in the MeV region with a sensitivity of the order 10(exp -5) photons/(sq cm s). During two observations periods in July 1992 and February 1993 the Galactic plane in the region of the young supernova remnant Cas A was observed, showing evidence for line emission at 1.16 MeV from the decay of Ti-44 at a significance level of approximately 4 sigma. This is the first time a supernova remnant has been detected in the gamma-ray line from Ti-44 decay. Adopting a distance of 2.8 kpc to the Cas A remnant, the measured line flux (7.0 +/- 1.7) x 10(exp -5) photons/(sq cm s), can be translated into a Ti-44 mass ejected during the Cas A supernova explosion, between (1.4 +/- 0.4) x 10(exp -4) solar mass and (3.2 +/- 0.8) x 10(exp -4) solar mass, depending on the precise value of the Ti-44 mean life time and on the precise date of the event. Implications of this result for supernova nucleosynthesis models are discussed.
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- 1994
132. COMPTEL gamma-ray observations of the quasars CTA 102 and 3C 454.3
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Blom, J. J, Bloemen, H, Bennett, K, Collmar, W, Hermsen, W, Mcconnell, M, Schoenfelder, V, Stacy, J. G, Steinle, H, and Strong, A
- Subjects
Astronomy - Abstract
The blazar-type active galactic nuclei CTA 102 (QSO 2230+114) and 3C 454.3 (QSO 2251+158), located about 7 deg apart, were observed by the Compton Gamma Ray Observatory at four epochs in 1992. Both were detected by Energy Gamma Ray Experiment Telescope (EGRET). The combined Compton Telescope (COMPTEL) observations in the 10-30 MeV energy range clearly indicate a source of MeV emission, which is likely due to a contribution from both quasars. These observations strongly suggest that the power-law spectra measured by EGRET above approximately 50 MeV flatten at lower MeV energies. A comparison with observations at other wavelengths shows that the power spectra of CTA 102 and 3C 454.3 peak at MeV energies. This behavior appears to be a common feature of gamma-ray active galactic nuclei (AGN).
- Published
- 1994
133. Comptel measurements of the gamma-ray burst GRB 930131
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Ryan, J, Bennett, K, Collmar, W, Connors, A, Fishman, G. J, Greiner, J, Hanlon, L. O, Hermsen, W, Kippen, R. M, and Kouveliotou, C
- Subjects
Astrophysics - Abstract
On 1993 January 31 at 1857:12 Universal Time (UT), the Imaging Compton Telescope COMPTEL onboard the Compton Gamma Ray Observatory (CGRO) detected the cosmic gamma-ray burst GRB 930131. COMPTEL's MeV imaging capability was employed to locate the source to better than 2 deg (1 sigma error radius) within 7 hr of the event, initiating a world-wide search for an optical and radio counterpart. The maximum likelihood position of the burst from the COMPTEL data is alpha(sub 2000) = 12h 18m, delta(sub 2000) = -9 deg 42 min, consistent with independent CGRO-Burst and Transient Source Experiment (CGRO-BATSE) and Energetic Gamma Ray Experiment Telescope (EGRET) locations as well as with the triangulation annulus constructed using BATSE and Ulysses timing data. The combined COMPTEL and EGRET burst data yield a better estimate of the burst location: alpha(sub 2000) = 12h 18m and delta(sub 2000) = -10 deg 21 min, with a 1 sigma error radius of 32 min. In COMPTEL's energy range, this burst was short, consisting of two separate spikes occurring within a approximately 1 s interval with a low intensity tail for approximately 1 s after the second spike. No statistically significant flux is present for a 30 s period after the main part of the burst. This is consistent with the EGRET data. The COMPTEL telescope events indicate a hard, power-law emission extending to beyond 10 MeV with a spectral index of -1.8 +/- 0.4. The rapid fluctuations and high intensities of the gamma-ray flux greater than 10 MeV place the burst object no farther than 250 pc if the burst emission is not beamed.
- Published
- 1994
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134. Emission from (super44)Ti associated with a previously unknown Galactic supernova
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Lyudin, A.F., Schonfelder, V., Bennett, K., Bloemen, H., Diehl, R., Hermsen, W., Lichti, G.G., van der Meulen, R.D., Ryan, J., and Winkler, C.
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Supernovae -- Research ,Environmental issues ,Science and technology ,Zoology and wildlife conservation - Abstract
The supernovae historical record is incomplete as shown by the spatial distribution f young supernova remnants. The discovery of gamma-ray emission from decay of (super44)Ti nuclei linked with Cassiopeia A, has provided a new method of searching for remnants of other comparatively recent supernovae. A (super44) line emission from a previously unknown supernova remnant has been discovered, with an estimated distance of 200 parsecs and age of 680 years.
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- 1998
135. Data analysis of the COMPTEL instrument on the NASA gamma ray observatory
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Diehl, R, Bennett, K, Collmar, W, Connors, A, Denherder, J. W, Hermsen, W, Lichti, G. G, Lockwood, J. A, Macri, J, and Mcconnell, M
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Astronomy - Abstract
The Compton imaging telescope (COMPTEL) on the Gamma Ray Observatory (GRO) is a wide field of view instrument. The coincidence measurement technique in two scintillation detector layers requires specific analysis methods. Straightforward event projection into the sky is impossible. Therefore, detector events are analyzed in a multi-dimensional dataspace using a gamma ray sky hypothesis convolved with the point spread function of the instrument in this dataspace. Background suppression and analysis techniques have important implications on the gamma ray source results for this background limited telescope. The COMPTEL collaboration applies a software system of analysis utilities, organized around a database management system. The use of this system for the assistance of guest investigators at the various collaboration sites and external sites is foreseen and allows different detail levels of cooperation with the COMPTEL institutes, dependent on the type of data to be studied.
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- 1992
136. Scientific objectives and first results from COMPTEL
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Schoenfelder, V, Bennett, K, Bloemen, H, Deboer, H, Busetta, M, Collmar, W, Connors, A, Diehl, R, Denherder, J. W, and Hermsen, W
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Astrophysics - Abstract
The imaging Compton telescope (COMPTEL) is the first imaging telescope in space to explore the MeV gamma ray range. At present it is performing a complete sky survey. In later phases of the mission, selected celestial objects will be studied in more detail. Targets of special interest in the COMPTEL energy range are radio pulsars, X-ray binaries, novae, supernova remnants, molecular clouds, and the interstellar medium within the Milky Way, as well as the nuclei of active galaxies, supernovae, and the diffuse cosmic background radiation in extragalactic space. The first four months of operation demonstrated that COMPTEL basically performs as expected. The Crab is clearly seen at its proper position in the first images of the anticenter region of the Galaxy. The Crab pulsar lightcurve was measured with unprecedented accuracy. The quasar 3C273 was seen for the first time at MeV-energies. Several cosmic bursts within the COMPTEL field of view could be located to an accuracy of about 1 degree. On June 9, 11, and 15, 1991 COMPTEL observed gamma ray (continuum and line) emission from three solar flares. Neutrons were also detected from the June 9 flare. At the present state of analysis, COMPTEL achieves the prelaunch predictions of its sensitivity within a factor of 2. Based on the present performance of COMPTEL, the team is confident that COMPTEL will fulfill its primary mission of surveying and exploring the MeV sky.
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- 1992
137. COMPTEL: Instrument description and performance
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Denherder, J. W, Aarts, H, Bennett, K, Deboer, H, Busetta, M, Collmar, W, Connors, A, Diehl, R, Hermsen, W, and Ryan, J
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Astronomy - Abstract
The imaging Compton telescope (COMPTEL) is one of the four gamma ray detectors aboard the Compton Gamma Ray Observatory (GRO). COMPTEL is sensitive to gamma rays from 800 keV to 30 MeV with a field of view of approximately 1 sr. Its angular resolution ranges between 1 and 2 degrees depending on the energy and incidence angle. The energy resolution of better than 10 percent FWHM enables COMPTEL to provide spectral resolution in the regime of astrophysical nuclear lines. The effective area varies typically from 10 to 50 cm(exp 2) depending on the energy and event selections made. In its telescope mode, COMPTEL is able to study a wide variety of objects, pointlike as well as extended in space. With 0.125 msec timing resolution, pulsed emission can be studied. In the single detector mode, COMPTEL uses two of its detectors to study the temporal spectral evolution of strong gamma ray bursts or transients.
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- 1992
138. COMPTEL solar flare observations
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Ryan, J. M, Aarts, H, Bennett, K, Debrunner, H, Devries, C, Denherder, J. W, Eymann, G, Forrest, D. J, Diehl, R, and Hermsen, W
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Solar Physics - Abstract
COMPTEL as part of a solar target of opportunity campaign observed the sun during the period of high solar activity from 7-15 Jun. 1991. Major flares were observed on 9 and 11 Jun. Although both flares were large GOES events (greater than or = X10), they were not extraordinary in terms of gamma-ray emission. Only the decay phase of the 15 Jun. flare was observed by COMPTEL. We report the preliminary analysis of data from these flares, including the first spectroscopic measurement of solar flare neutrons. The deuterium formation line at 2.223 MeV was present in both events and for at least the 9 Jun. event, was comparable to the flux in the nuclear line region of 4-8 MeV, consistent with Solar-Maximum Mission (SSM) Observations. A clear neutron signal was present in the flare of 9 Jun. with the spectrum extending up to 80 MeV and consistent in time with the emission of gamma-rays, confirming the utility of COMPTEL in measuring the solar neutron flux at low energies. The neutron flux below 100 MeV appears to be lower than that of the 3 Jun. 1982 flare by more than an order of magnitude. The neutron signal of the 11 Jun. event is under study. Severe dead time effects resulting from the intense thermal x-rays require significant corrections to the measured flux which increase the magnitude of the associated systematic uncertainties.
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- 1992
139. Discovery of synchronous X-ray and radio moding of PSR B0823+26
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Hermsen, W, primary, Kuiper, L, additional, Basu, R, additional, Hessels, J W T, additional, Mitra, D, additional, Rankin, J M, additional, Stappers, B W, additional, Wright, G A E, additional, Grießmeier, J-M, additional, Serylak, M, additional, Horneffer, A, additional, Tiburzi, C, additional, and Ho, W C G, additional
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- 2018
- Full Text
- View/download PDF
140. More data on (possible) gamma ray (point) sources
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Hermsen, W
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Space Radiation - Abstract
The 2CG catalog of gamma ray sources was compiled before detailed knowledge was available on the fine-scale structure of the diffuse Galactic gamma-ray emission. Two independent analyses to discriminate sources which are either compact objects of due to very local and strong enhancements in the Galactic cosmic-ray distribution from those which are artifacts due to the clumpy gas distribution are about to be completed: a maximum likelihood analysis and a cross correlation analysis. Arguments are given why differences, and therefore confusion, and in resulting source lists can be expected. Detailed analysis of all COS-B gamma-ray data on Geminga (2CG195+04), reveals the existence of a drastic spectral break below 200 MeV. A power-law spectrum with index -1.88 fits the data above about 100 MeV to 3.2 GeV, however, there are also indications for a spectral break above these energies. For energies above about 100 MeV no evidence for a long-term time variability was found. The error region of Geminga was searched for a radio counterpart at wavelengths of 90, 49, 21, 6, and 2 cm using the Westerbork Synthesis Radio Telescope and the Very Large Array. So far, 16 sources were detected in this error region. In the direction of 1E0630+178, the Einstein x ray source proposed to be a Vela-like pulsar and the counterpart of Geminga, no radio source was found at 21, 49, and 90 cm with 3 sigma upper limits on the flux densities ranging from 0.5 mJy at 21 cm to 4.5 mJy at 90 cm. Detailed structures in local molecular cloud complexes are so far only resolved in gamma rays for the closet and most massive complexes, namely those in the Orion-Monoceros and the Ophiuchus regions. For both region, there is circumstantial evidence for gamma ray emission from molecular gas that was photodissociated after the passage of a SN shell.
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- 1990
141. The Fermi-LAT detection of magnetar-like pulsar PSR J1846−0258 at high-energy gamma-rays
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Kuiper, L, primary, Hermsen, W, additional, and Dekker, A, additional
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- 2017
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142. X-ray properties of the mode-switching pulsar PSR B0943+10
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Mereghetti, S, primary, Kuiper, L, additional, Tiengo, A, additional, Hessels, J, additional, Hermsen, W, additional, Stovall, K, additional, Possenti, A, additional, Rankin, J, additional, Esposito, P, additional, Turolla, R, additional, Mitra, D, additional, Wright, G, additional, Stappers, B, additional, Horneffer, A, additional, Oslowski, S, additional, Serylak, M, additional, Griessmeier, J-M, additional, and Rigoselli, M, additional
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- 2017
- Full Text
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143. Centaurus A: Multiwavelength observations of the nearest active galaxy from radio to gamma-rays
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Steinle, H, Bonnell, J, Kinzer, R.L, Tzioumis, A, Bignall, H, Schönfelder, V, Bennett, K, Hermsen, W, and Ryan, J
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- 1999
- Full Text
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144. ORIGIN: metal creation and evolution from the cosmic dawn
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den, Herder Jan-Willem, Piro, Luigi, Kouveliotou, Chryssa, Hartmann, Dieter H., Kaastra, Jelle S., Amati, L., Andersen, M. I., Arnaud, M., Atteia, J.-L., Bandler, S., Barbera, M., Barcons, X., Barthelmy, S., Basa, S., Basso, S., Boer, M., Branchini, E., Branduardi-Raymont, G., Borgani, S., Boyarsky, A., Brunetti, G., Budtz-Jorgensen, C., Burrows, D., Butler, N., Campana, S., Caroli, E., Ceballos, M., Christensen, F., Churazov, E., Comastri, A., Colasanti, L., Cole, R., Content, R., Corsi, A., Costantini, E., Conconi, P., Cusumano, G., de, Plaa J., De, Rosa A., Del, Santo M., Di, Cosimo S., De, Pasquale M., Doriese, R., Ettori, S., Evans, P., Ferrari, L., Finger, H., Figueroa-Feliciano, T., Friedrich, P., Furuzawa, A., Fynbo, J., Gatti, F., Galeazzi, M., Gehrels, N., Gendre, B., Ghirlanda, G., Ghisellini, G., Gilfanov, M., Giommi, P., Girardi, M., Grindlay, J., Cocchi, M., Godet, O., Guedel, M., Haardt, F., den, Hartog R., Hepburn, I., Hermsen, W., Hjorth, J., Hoekstra, H., Holland, A., Hornstrup, A., van, der Horst A., int, Zand J., Irwin, K., Jonker, P., Kitayama, T., Kawahara, H., Kawai, N., Kelley, R., Kilbourne, C., de, Korte P., Kusenko, A., Kuvvetli, I., Labanti, M., Macculi, C., Maiolino, R., Mas, Hesse M., Matsushita, K., Mazzotta, P., McCammon, D., Mendez, M., Mignani, R., Mineo, T., Mushotzky, R., Molendi, S., Moscardini, L., Natalucci, L., Nicastro, F., O'Brien, P., Osborne, J., Paerels, F., Page, M., Paltani, S., Pedersen, K., Perinati, E., Ponman, T., Pointecouteau, E., Predehl, P., Porter, S., Rasmussen, A., Rauw, G., Rottgering, H., Roncarelli, M., Rosati, P., Quadrini, E., Ruchayskiy, O., Salvaterra, R., Sasaki, S., Sato, K., Savaglio, S., Schaye, J., Sciortino, S., Shaposhnikov, M., Sharples, R., Shinozaki, K., Spiga, D., Sunyaev, R., Suto, Y., Tanvir, N., Troja, E., Ubertini, P., Ullom, J., Ursino, E., Verbunt, F., van, de Voort F., Viel, M., Wachter, S., Watson, D., Weisskopf, M., Werner, N., White, N., Willingale, R., Wijers, R., Yoshikawa, K., Zane, S., Ohashi, Takaya, Ezoe, Y., Fujimoto, R., Hoshino, A., Ishisaki, Y., Mitsuda, Kazuhisa, Takei, Yoh, Tashiro, Makoto, Tamura, Takayuki, Tawara, Yuzuru, Tsujimoto, Masahiro, Tsuru, Takeshi, Yamasaki, Noriko, den Herder, JW, Piro, L, Ohashi, T, Kouveliotou, C, Hartmann, DH, Kaastra, JS, Amati, L, Andersen, MI, Arnaud, M, Attèia, JL, Bandler, S, Barbera, M, Barcons, X, Barthelmy, S, Basa, S, Basso, S, Boer, M, Branchini, E, Branduardi-Raymont, G, Borgani, S, Boyarsky, A, Brunetti, G, Budtz-Jorgensen, C, Burrows, D, Butler, N, Campana, S, Caroli, E, Ceballos, M, Christensen, F, Churazov, E, Comastri, A, Colasanti, L, Cole, R, Content, R, Corsi, A, Costantini, E, Conconi, P, Cusumano, G, de Plaa, J, De Rosa, A, Del Santo, M, Di Cosimo, S, De Pasquale, M, Doriese, R, Ettori, S, Evans, P, Ezoe, Y, Ferrari, L, Finger, H, Figueroa-Feliciano, T, Friedrich, P, Fujimoto, R, Furuzawa, A, Fynbo, J, Gatti, F, Galeazzi, M, Gehrels, N, Gendre, B, Ghirlanda, G, Ghisellini, G, Gilfanov, M, Giommi, P, Girardi, M, Grindlay, J, Cocchi, M, Godet, O, Guedel, M, Haardt, F, den Hartog, R, Hepburn, I, Hermsen, W, Hjorth, J, Hoekstra, H, Holland, A, Hornstrup, A, van der Horst, A, Hoshino, A, in't Zand, J, Irwin, K, Ishisaki, Y, Jonker, P, Kitayama, T, Kawahara, H, Kawai, N, Kelley, R, Kilbourne, C, de Korte, P, Kusenko, A, Kuvvetli, I, Labanti, M, Macculi, C, Maiolino, R, Hesse, MM, Matsushita, K, Mazzotta, P, McCammon, D, Mèndez, M, Mignani, R, Mineo, T, Mitsuda, K, Mushotzky, R, Molendi, S, Moscardini, L, Natalucci, L, Nicastro, F, O'Brien, P, Osborne, J, Paerels, F, Page, M, Paltani, S, Pedersen, K, Perinati, E, Ponman, T, Pointecouteau, E, Predehl, P, Porter, S, Rasmussen, A, Rauw, G, Rottgering, H, Roncarelli, M, Rosati, P, Quadrini, E, Ruchayskiy, O, Salvaterra, R, Sasaki, S, Sato, K, Savaglio, S, Schaye, J, Sciortino, S, Shaposhnikov, M, Sharples, R, Shinozaki, K, Spiga, D, Sunyaev, R, Suto, Y, Takei, Y, Tanvir, N, Tashiro, M, Tamura, T, Tawara, Y, Troja, E, Tsujimoto, M, Tsuru, T, Ubertini, P, Ullom, J, Ursino, E, Verbunt, F, van de Voort, F, Viel, M, Wachter, S, Watson, D, Weisskopf, M, Werner, N, White, N, Willingale, R, Wijers, R, Yamasaki, N, Yoshikawa, K, Zane, S, Airbus, High Energy Astrophys. & Astropart. Phys (API, FNWI), Massachusetts Institute of Technology. Department of Physics, Figueroa-Feliciano, Enectali, Astronomy, J. W., den Herder, L., Piro, T., Ohashi, C., Kouveliotou, D. H., Hartmann, J. S., Kaastra, L., Amati, M. I., Andersen, M., Arnaud, J. L., Attéia, S., Bandler, M., Barbera, X., Barcon, S., Barthelmy, S., Basa, S., Basso, M., Boer, E., Branchini, G., Branduardi Raymont, Borgani, Stefano, A., Boyarsky, G., Brunetti, C., Budtz Jorgensen, D., Burrow, N., Butler, S., Campana, E., Caroli, M., Ceballo, F., Christensen, E., Churazov, A., Comastri, L., Colasanti, R., Cole, R., Content, A., Corsi, E., Costantini, P., Conconi, G., Cusumano, J., de Plaa, A., De Rosa, M., Del Santo, S., Di Cosimo, M., De Pasquale, R., Doriese, S., Ettori, P., Evan, Y., Ezoe, L., Ferrari, H., Finger, T., Figueroa Feliciano, P., Friedrich, R., Fujimoto, A., Furuzawa, J., Fynbo, F., Gatti, M., Galeazzi, N., Gehrel, B., Gendre, G., Ghirlanda, G., Ghisellini, M., Gilfanov, P., Giommi, Girardi, Marisa, J., Grindlay, M., Cocchi, O., Godet, M., Guedel, F., Haardt, R., den Hartog, I., Hepburn, W., Hermsen, J., Hjorth, H., Hoekstra, A., Holland, A., Hornstrup, A., van der Horst, A., Hoshino, J. in t., Zand, K., Irwin, Y., Ishisaki, P., Jonker, T., Kitayama, H., Kawahara, N., Kawai, R., Kelley, C., Kilbourne, P., de Korte, A., Kusenko, I., Kuvvetli, M., Labanti, C., Macculi, R., Maiolino, M., Mas Hesse, K., Matsushita, P., Mazzotta, D., Mccammon, M., Méndez, R., Mignani, T., Mineo, K., Mitsuda, R., Mushotzky, S., Molendi, L., Moscardini, L., Natalucci, F., Nicastro, P. O., Brien, J., Osborne, F., Paerel, M., Page, S., Paltani, K., Pedersen, E., Perinati, T., Ponman, E., Pointecouteau, P., Predehl, S., Porter, A., Rasmussen, G., Rauw, H., Röttgering, M., Roncarelli, P., Rosati, E., Quadrini, O., Ruchayskiy, R., Salvaterra, S., Sasaki, K., Sato, S., Savaglio, J., Schaye, S., Sciortino, M., Shaposhnikov, R., Sharple, K., Shinozaki, D., Spiga, R., Sunyaev, Y., Suto, Y., Takei, N., Tanvir, M., Tashiro, T., Tamura, Y., Tawara, E., Troja, M., Tsujimoto, T., Tsuru, P., Ubertini, J., Ullom, E., Ursino, F., Verbunt, F., van de Voort, M., Viel, S., Wachter, D., Watson, M., Weisskopf, N., Werner, N., White, R., Willingale, R., Wijer, N., Yamasaki, K., Yoshikawa, S., Zane, Jan-Willem Herder, Luigi Piro, Takaya Ohashi, Chryssa Kouveliotou, Dieter H. Hartmann, Jelle S. Kaastra, L. Amati, M. I. Andersen, M. Arnaud, J. -L. Attéia, S. Bandler, M. Barbera, X. Barcon, S. Barthelmy, S. Basa, S. Basso, M. Boer, E. Branchini, G. Branduardi-Raymont, S. Borgani, A. Boyarsky, G. Brunetti, C. Budtz-Jorgensen, D. Burrow, N. Butler, S. Campana, E. Caroli, M. Ceballo, F. Christensen, E. Churazov, A. Comastri, L. Colasanti, R. Cole, R. Content, A. Corsi, E. Costantini, P. Conconi, G. Cusumano, J. Plaa, A. Rosa, M. Santo, S. Cosimo, M. Pasquale, R. Doriese, S. Ettori, P. Evan, Y. Ezoe, L. Ferrari, H. Finger, T. Figueroa-Feliciano, P. Friedrich, R. Fujimoto, A. Furuzawa, J. Fynbo, F. Gatti, M. Galeazzi, N. Gehrel, B. Gendre, G. Ghirlanda, G. Ghisellini, M. Gilfanov, P. Giommi, M. Girardi, J. Grindlay, M. Cocchi, O. Godet, M. Guedel, F. Haardt, R. Hartog, I. Hepburn, W. Hermsen, J. Hjorth, H. Hoekstra, A. Holland, A. Hornstrup, A. Horst, A. Hoshino, J. Zand, K. Irwin, Y. Ishisaki, P. Jonker, T. Kitayama, H. Kawahara, N. Kawai, R. Kelley, C. Kilbourne, P. Korte, A. Kusenko, I. Kuvvetli, M. Labanti, C. Macculi, R. Maiolino, M. Mas Hesse, K. Matsushita, P. Mazzotta, D. McCammon, M. Méndez, R. Mignani, T. Mineo, K. Mitsuda, R. Mushotzky, S. Molendi, L. Moscardini, L. Natalucci, F. Nicastro, P. O’Brien, J. Osborne, F. Paerel, M. Page, S. Paltani, K. Pedersen, E. Perinati, T. Ponman, E. Pointecouteau, P. Predehl, S. Porter, A. Rasmussen, G. Rauw, H. Röttgering, M. Roncarelli, P. Rosati, E. Quadrini, O. Ruchayskiy, R. Salvaterra, S. Sasaki, K. Sato, S. Savaglio, J. Schaye, S. Sciortino, M. Shaposhnikov, R. Sharple, K. Shinozaki, D. Spiga, R. Sunyaev, Y. Suto, Y. Takei, N. Tanvir, M. Tashiro, T. Tamura, Y. Tawara, E. Troja, M. Tsujimoto, T. Tsuru, P. Ubertini, J. Ullom, E. Ursino, F. Verbunt, F. Voort, M. Viel, S. Wachter, D. Watson, M. Weisskopf, N. Werner, N. White, R. Willingale, R. Wijer, N. Yamasaki, K. Yoshikawa, S. Zane, den Herder Jan, Willem, Piro, Luigi, Ohashi, Takaya, Kouveliotou, Chryssa, Hartmann Dieter, H., Kaastra Jelle, S., Amati, L., Andersen, M. I., Arnaud, M., Atteia, J. L., Bandler, S., Barbera, M., Barcons, X., Barthelmy, S., Basa, S., Basso, S., Boer, M., Branchini, ENZO FRANCO, Branduardi Raymont, G., Borgani, S., Boyarsky, A., Brunetti, G., Budtz Jorgensen, C., Burrows, D., Butler, N., Campana, S., Caroli, E., Ceballos, M., Christensen, F., Churazov, E., Comastri, A., Colasanti, L., Cole, R., Content, R., Corsi, A., Costantini, E., Conconi, P., Cusumano, G., de Plaa, J., De Rosa, A., Del Santo, M., Di Cosimo, S., De Pasquale, M., Doriese, R., Ettori, S., Evans, P., Ezoe, Y., Ferrari, L., Finger, H., Figueroa Feliciano, T., Friedrich, P., Fujimoto, R., Furuzawa, A., Fynbo, J., Gatti, F., Galeazzi, M., Gehrels, N., Gendre, B., Ghirlanda, G., Ghisellini, G., Gilfanov, M., Giommi, P., Girardi, M., Grindlay, J., Cocchi, M., Godet, O., Guedel, M., Haardt, F., den Hartog, R., Hepburn, I., Hermsen, W., Hjorth, J., Hoekstra, H., Holland, A., Hornstrup, A., van der Horst, A., Hoshino, A., in't Zand, J., Irwin, K., Ishisaki, Y., Jonker, P., Kitayama, T., Kawahara, H., Kawai, N., Kelley, R., Kilbourne, C., de Korte, P., Kusenko, A., Kuvvetli, I., Labanti, M., Macculi, C., Maiolino, R., Mas Hesse, M., Matsushita, K., Mazzotta, P., Mccammon, D., Mendez, M., Mignani, R., Mineo, T., Mitsuda, K., Mushotzky, R., Molendi, S., Moscardini, L., Natalucci, L., Nicastro, F., O'Brien, P., Osborne, J., Paerels, F., Page, M., Paltani, S., Pedersen, K., Perinati, E., Ponman, T., Pointecouteau, E., Predehl, P., Porter, S., Rasmussen, A., Rauw, G., Rottgering, H., Roncarelli, M., Rosati, P., Quadrini, E., Ruchayskiy, O., Salvaterra, R., Sasaki, S., Sato, K., Savaglio, S., Schaye, J., Sciortino, S., Shaposhnikov, M., Sharples, R., Shinozaki, K., Spiga, D., Sunyaev, R., Suto, Y., Takei, Y., Tanvir, N., Tashiro, M., Tamura, T., Tawara, Y., Troja, E., Tsujimoto, M., Tsuru, T., Ubertini, P., Ullom, J., Ursino, E., Verbunt, F., van de Voort, F., Viel, M., Wachter, S., Watson, D., Weisskopf, M., Werner, N., White, N., Willingale, R., Wijers, R., Yamasaki, N., Yoshikawa, K., and Zane, S.
- Subjects
HOT INTERGALACTIC MEDIUM ,UNIVERSE ,Chemical evolution ,Mission ,7. Clean energy ,01 natural sciences ,Spectral line ,Settore FIS/05 - Astronomia E Astrofisica ,010303 astronomy & astrophysics ,media_common ,Physics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,NUCLEOSYNTHESIS ,COSMIC cancer database ,Clusters of galaxies ,Satellite Mission ,Epoch (reference date) ,Astrophysics::Instrumentation and Methods for Astrophysics ,FOREST ,GALAXIES ,Gamma-ray bursts ,Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena ,X-ray, Mission, Gamma-ray bursts, Clusters of galaxies, Warm-hot intergalactic medium, Chemical evolution ,Warm-hot intergalactic medium ,Astrophysics - Cosmology and Nongalactic Astrophysics ,Astrophysics and Astronomy ,Structure formation ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Clusters of galaxie ,media_common.quotation_subject ,Astrophysics::High Energy Astrophysical Phenomena ,REDSHIFT ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,X-ray Mission, Gamma-ray bursts, Clusters of galaxies, Warm-hot intergalactic medium, Chemical evolution ,ABSORPTION-SPECTRA ,010309 optics ,X-ray ,YIELDS ,0103 physical sciences ,Gamma-ray burst ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Astronomy ,Astronomy and Astrophysics ,Redshift ,Galaxy ,Universe ,13. Climate action ,Space and Planetary Science ,CLUSTERS - Abstract
Herder, Jan-Willem den et al., ORIGIN is a proposal for the M3 mission call of ESA aimed at the study of metal creation from the epoch of cosmic dawn. Using high-spectral resolution in the soft X-ray band, ORIGIN will be able to identify the physical conditions of all abundant elements between C and Ni to red-shifts of z = 10, and beyond. The mission will answer questions such as: When were the first metals created? How does the cosmic metal content evolve? Where do most of the metals reside in the Universe? What is the role of metals in structure formation and evolution? To reach out to the early Universe ORIGIN will use Gamma-Ray Bursts (GRBs) to study their local environments in their host galaxies. This requires the capability to slew the satellite in less than a minute to the GRB location. By studying the chemical composition and properties of clusters of galaxies we can extend the range of exploration to lower redshifts (z-0.2). For this task we need a high-resolution spectral imaging instrument with a large field of view. Using the same instrument, we can also study the so far only partially detected baryons in the Warm-Hot Intergalactic Medium (WHIM). The less dense part of the WHIM will be studied using absorption lines at low redshift in the spectra for GRBs. The ORIGIN mission includes a Transient Event Detector (coded mask with a sensitivity of 0.4 photon/cm2/s in 10 s in the 5–150 keV band) to identify and localize 2000 GRBs over a five year mission, of which -65 GRBs have a redshift > 7. The Cryogenic Imaging Spectrometer, with a spectral resolution of 2.5 eV, a field of view of 30 arcmin and large effective area below 1 keV has the sensitivity to study clusters up to a significant fraction of the virial radius and to map the denser parts of the WHIM (factor 30 higher than achievable with current instruments). The payload is complemented by a Burst InfraRed Telescope to enable onboard red-shift determination of GRBs (hence securing proper follow up of high-z bursts) and also probes the mildly ionized state of the gas. Fast repointing is achieved by a dedicated ControlledMomentum Gyro and a low background is achieved by the selected low Earth orbit., The team likes to express its appreciation for the support of Astrium UK for the present study.
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- 2011
145. COMPASS: the COMPTEL Processing and Analysis Software Software System
- Author
-
Diehl, R., Simpson, G., Casilli, T., Schoenfelder, V., Lichti, G., Steinle, H., Swanenburg, B., Aarts, H., Deerenberg, A., Hermsen, W., Bennett, K., Winkler, C., Snelling, M., Lockwood, J., Morris, D., Ryan, J., Zichichi, Antonino, editor, Di Gesù, V., editor, Scarsi, L., editor, Crane, P., editor, Friedman, J. H., editor, and Levialdi, S., editor
- Published
- 1986
- Full Text
- View/download PDF
146. High-Energy Gamma Rays and the Large-Scale Distribution of Gas and Cosmic Rays
- Author
-
Hermsen, W., Bloemen, J. B. G. M., Van Woerden, Hugo, editor, Allen, Ronald J., editor, and Burton, W. Butler, editor
- Published
- 1985
- Full Text
- View/download PDF
147. The Large-Scale Distribution of Galactic Gamma-Ray Emission
- Author
-
Hermsen, W., Bloemen, J. B. G. M., Burton, W. B., editor, and Israel, F. P., editor
- Published
- 1983
- Full Text
- View/download PDF
148. On the Radial Distribution of Gamma Rays in the Outer Galaxy
- Author
-
Bloemen, J. B. G. M., Blitz, L., Hermsen, W., Burton, W. B., editor, and Israel, F. P., editor
- Published
- 1983
- Full Text
- View/download PDF
149. Production Sites and Mechanisms of Discrete Gamma-Ray Components of the Vela and Crab Light Curves
- Author
-
Hermsen, W., Grenier, I. A., Ögelman, H., editor, and van den Heuvel, E. P. J., editor
- Published
- 1989
- Full Text
- View/download PDF
150. Gamma-Ray Sources Observed by Cos-B
- Author
-
Hermsen, W., Morfill, G. E., editor, and Buccheri, R., editor
- Published
- 1983
- Full Text
- View/download PDF
Catalog
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