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39 results on '"Gers, L"'

1. On-sky commissioning of MAROON-X: A new precision radial velocity spectrograph for Gemini North

Author

Seifahrt, A., Bean, J. L., Stürmer, J., Kasper, D., Gers, L., Schwab, C., Zechmeister, M., Stefánsson, G., Montet, B., Santos, L. A. Dos, Peck, A., White, J., and Tapia, E.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

MAROON-X is a fiber-fed, red-optical, high precision radial velocity spectrograph recently commissioned at the Gemini North telescope on Mauna Kea, Hawai'i. With a resolving power of 85,000 and a wavelength coverage of 500-920 nm, it delivers radial velocity measurements for late K and M dwarfs with sub-50 cm s$^{-1}$ precision. MAROON-X is currently the only optical EPRV spectrograph on a 8m-class telescope in the northern hemisphere and the only EPRV instrument on a large telescope with full access by the entire US community. We report here on the results of the commissioning campaign in December 2019 and early science results., Comment: 21 pages, 14 figures

Published
2021
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2. Suppression of the near-infrared OH night sky lines with fibre Bragg gratings - first results

Author

Ellis, S. C., Bland-Hawthorn, J., Lawrence, J., Horton, A. J., Trinh, C., Leon-Saval, S. G., Shortridge, K., Bryant, J., Case, S., Colless, M., Couch, W., Freeman, K., Gers, L., Glazebrook, K., Haynes, R., Lee, S., Loehmannsroeben, H. -G., Byrne, J. O., Miziarski, S., Roth, M., Schmidt, B., Tinney, C. G., and Zheng, J.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

The background noise between 1 and 1.8 microns in ground-based instruments is dominated by atmospheric emission from hydroxyl molecules. We have built and commissioned a new instrument, GNOSIS, which suppresses 103 OH doublets between 1.47 - 1.7 microns by a factor of ~1000 with a resolving power of ~10,000. We present the first results from the commissioning of GNOSIS using the IRIS2 spectrograph at the AAT. The combined throughput of the GNOSIS fore-optics, grating unit and relay optics is ~36 per cent, but this could be improved to ~46 per cent with a more optimal design. We measure strong suppression of the OH lines, confirming that OH suppression with fibre Bragg gratings will be a powerful technology for low resolution spectroscopy. The integrated OH suppressed background between 1.5 and 1.7 microns is reduced by a factor of 9 compared to a control spectrum using the same system without suppression. The potential of low resolution OH suppressed spectroscopy is illustrated with example observations. The GNOSIS background is dominated by detector dark current below 1.67 microns and by thermal emission above 1.67 microns. After subtracting these we detect an unidentified residual interline component of ~ 860 +/ 210 ph/s/m^2/micron/arcsec^2. This component is equally bright in the suppressed and control spectra. We have investigated the possible source of the interline component, but were unable to discriminate between a possible instrumental artifact and intrinsic atmospheric emission. Resolving the source of this emission is crucial for the design of fully optimised OH suppression spectrographs. The next generation OH suppression spectrograph will be focussed on resolving the source of the interline component, taking advantage of better optimisation for a FBG feed. We quantify the necessary improvements for an optimal OH suppressing fibre spectrograph design., Comment: Accepted for publication in MNRAS. 15 pages, 18 figures

Published
2012
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3. Adaptive optics at W. M. Keck Observatory

Author

Jackson, Kathryn J., Schmidt, Dirk, Vernet, Elise, Wizinowich, P., Bouchez, A., Marin, E., Cetre, S., Chin, J., Correia, C., van Dam, M., Delorme, J.-R., Gers, L., Guthery, C., Karkar, S., Kwok, S., Lilley, S., Lyke, J., Richards, P., Service, M., Steiner, J., Surendran, A., Tsubota, K., Wetherell, E., Bottom, M., Dekany, R., Ghez, A., Hinz, P., Liu, M., Lu, J., Jensen-Clem, R., Millar-Blanchaer, M., Peretz, E., Sallum, S., Treu, T., and Wright, S.

Published
2024
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4. Keck All sky Precision Adaptive optics program overview

Author

Schreiber, Laura, Schmidt, Dirk, Vernet, Elise, Wizinowich, P., Lu, J. R., Cetre, S., Chin, J., Correia, C., Delorme, J.-R., Gers, L., Lilley, S., Lyke, J., Marin, E., Ragland, S., Richards, P., Surendran, A., Wetherell, E., Chen, C.-F., Chu, D., Do, T., Fassnacht, C., Freeman, M., Gautam, A., Ghez, A., Hunter, L., Jones, T., Liu, M. C., Mawet, D., Max, C., Morris, M., Phillips, M., Ruffio, J.-B., Rundquist, N.-E., Sabhlok, S., Terry, S., Treu, T., and Wright, S.

Published
2022
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6. Design evolution of the Giant Magellan Telescope Integral Field Spectrograph, GMTIFS

Author

Sharp, Robert G., primary, Bloxham, Gabe, primary, Boz, Robert, primary, Bundy, Dave, primary, Gausachs, Gaston, primary, Hart, John, primary, Herrald, Nicholas, primary, Nielsen, Jon, primary, O'Brien, Ellie, primary, Onken, Chris, primary, Price, Ian, primary, Vaccarella, Annino, primary, Vest, Colin, primary, Young, Peter, primary, Chandler, D., primary, Gers, L., primary, and Adams, D., primary

Published
2018
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8. Keck all sky precision adaptive optics

Author

Schreiber, Laura, Schmidt, Dirk, Vernet, Elise, Wizinowich, P., Chin, J., Correia, C., Lu, J., Brown, T., Casey, K., Cetre, S., Delorme, J.-R., Gers, L., Hunter, L., Lilley, S., Ragland, S., Surendran, A., Wetherell, E., Ghez, A., Do, T., Jones, T., Liu, M., Mawet, D., Max, C., Morris, M., Treu, T., and Wright, S.

Published
2020
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10. First light results from the Hermes spectrograph at the AAT

Author

Sheinis, A., Barden, S., Birchall, M., Carollo, D., Bland-Hawthorn, J., Brzeski, J., Case, S., Cannon, R., Churilov, V., Couch, W., Dean, R., De Silva, G., D'Orazi, V., Farrell, T., Fiegert, K., Freeman, K., Frost, G., Gers, L., Goodwin, M., Gray, D., Heald, R., Heijmans, J.A.C., Jones, D., Keller, S., Klauser, U., Kondrat, Y., Lawrence, J., Lee, S., Mali, S., Martell, S., Mathews, D., Mayfield, D., Miziarski, S., Muller, R., Pai, N., Patterson, R., Penny, E., Orr, D., Shortridge, K., Simpson, J., Smedley, S., Smith, G., Stafford, D., Staszak, N., Vuong, M., Waller, L., Wylie de Boer, E., Xavier, P., Zheng, J., Zhelem, R., and Zucker, D.

Subjects
VPH, OM - Opto-Mechatronics, TS - Technical Sciences, Signal to noise ratio, Industrial Innovation, GALAH, Astronomy, HERMES, High Tech Systems & Materials, Surveys, Galaxies, Stars, 2dF, AAT, Fibers, Spectrographs, Nano Technology
Abstract

The High Efficiency and Resolution Multi Element Spectrograph, HERMES is an facility-class optical spectrograph for the AAT. It is designed primarily for Galactic Archeology [21], the first major attempt to create a detailed understanding of galaxy formation and evolution by studying the history of our own galaxy, the Milky Way. The goal of the GALAH survey is to reconstruct the mass assembly history of the of the Milky Way, through a detailed spatially tagged abundance study of one million stars. The spectrograph is based at the Anglo Australian Telescope (AAT) and is fed by the existing 2dF robotic fiber positioning system. The spectrograph uses VPH-gratings to achieve a spectral resolving power of 28,000 in standard mode and also provides a high-resolution mode ranging between 40,000 to 50,000 using a slit mask. The GALAH survey requires a SNR greater than 100 for a star brightness of V=14. The total spectral coverage of the four channels is about 100nm between 370 and 1000nm for up to 392 simultaneous targets within the 2 degree field of view. Hermes has been commissioned over 3 runs, during bright time in October, November and December 2013, in parallel with the beginning of the GALAH Pilot survey starting in November 2013. In this paper we present the first-light results from the commissioning run and the beginning of the GALAH Survey, including performance results such as throughput and resolution, as well as instrument reliability. We compare the abundance calculations from the pilot survey to those in the literature.

Published
2014

12. First light results from the High Efficiency and Resolution Multi-Element Spectrograph at the Anglo-Australian Telescope

Author

Sheinis, A, Anguiano, B, Asplund, M, Bacigalupo, C, Barden, S, Birchall, M, Bland-Hawthorn, J, Brzeski, J, Cannon, R, Carollo, D, Case, S, Casey, A, Churilov, V, Warrick, C, Dean, R, De Silva, G, D'Orazi, V, Duong, L, Farrell, T, Fiegert, K, Freeman, K, Gabriella, F, Gers, L, Goodwin, M, Gray, D, Green, A, Heald, R, Heijmans, J, Ireland, M, Jones, D, Kafle, P, Keller, S, Klauser, U, Kondrat, Y, Kos, J, Lawrence, J, Lee, S, Mali, S, Martell, S, Mathews, D, Mayfield, D, Miziarski, S, Muller, R, Pai, N, Patterson, R, Penny, E, Orr, D, Schlesinger, K, Sharma, S, Shortridge, K, Simpson, J, Smedley, S, Smith, G, Stafford, D, Staszak, N, Vuong, M, Waller, L, de Boer, EW, Xavier, P, Zheng, J, Zhelem, R, Zucker, D, Zwitter, T, Sheinis, A, Anguiano, B, Asplund, M, Bacigalupo, C, Barden, S, Birchall, M, Bland-Hawthorn, J, Brzeski, J, Cannon, R, Carollo, D, Case, S, Casey, A, Churilov, V, Warrick, C, Dean, R, De Silva, G, D'Orazi, V, Duong, L, Farrell, T, Fiegert, K, Freeman, K, Gabriella, F, Gers, L, Goodwin, M, Gray, D, Green, A, Heald, R, Heijmans, J, Ireland, M, Jones, D, Kafle, P, Keller, S, Klauser, U, Kondrat, Y, Kos, J, Lawrence, J, Lee, S, Mali, S, Martell, S, Mathews, D, Mayfield, D, Miziarski, S, Muller, R, Pai, N, Patterson, R, Penny, E, Orr, D, Schlesinger, K, Sharma, S, Shortridge, K, Simpson, J, Smedley, S, Smith, G, Stafford, D, Staszak, N, Vuong, M, Waller, L, de Boer, EW, Xavier, P, Zheng, J, Zhelem, R, Zucker, D, and Zwitter, T

Published
2015

13. The MANIFEST fibre positioning system for the Giant Magellan Telescope

Author

Lawrence, J S, Brown, David, Brzeski, Jurek, Case, S, Colless, Matthew, Farrell, Tony, Gers, L, Gilbert, James, Goodwin, Michael, Jacoby, George H, Hopkins, Andrew M., Ireland, Michael, Lawrence, J S, Brown, David, Brzeski, Jurek, Case, S, Colless, Matthew, Farrell, Tony, Gers, L, Gilbert, James, Goodwin, Michael, Jacoby, George H, Hopkins, Andrew M., and Ireland, Michael

Published
2014

14. TAIPAN: Optical spectroscopy with StarBugs

Author

Kuehn, Kyler, Lawrence, J, Brown, David, Case, S, Colless, Matthew, Gers, L, Richards, Samuel, Saunders, Will, Staszak, N, Tims, J, Waller, Lew, Ireland, Michael, Kuehn, Kyler, Lawrence, J, Brown, David, Case, S, Colless, Matthew, Gers, L, Richards, Samuel, Saunders, Will, Staszak, N, Tims, J, Waller, Lew, and Ireland, Michael

Abstract

TAIPAN is a spectroscopic instrument designed for the UK Schmidt Telescope at the Australian Astronomical Observatory. In addition to undertaking the TAIPAN survey, it will serve as a prototype for the MANIFEST fibre positioner system for the future Giant Magellan Telescope. The design for TAIPAN incorporates up to 300 optical fibres situated within independently-controlled robotic positioners known as Starbugs, allowing precise parallel positioning of every fibre, thus significantly reducing instrument configuration time and increasing observing time. We describe the design of the TAIPAN instrument system, as well as the science that will be accomplished by the TAIPAN survey. We also highlight results from the on-sky tests performed in May 2014 with Starbugs on the UK Schmidt Telescope and briefly introduce the role that Starbugs will play in MANIFEST.

Published
2014

15. First light results from the Hermes spectrograph at the AAT

Author

Sheinis, Andrew, Barden, Sam, Birchall, Michael, Carollo, Daniela, Bland-Hawthorn, Joss, Brzeski, Jurek, Case, S, Cannon, R. D., Churilov, Vladimir, Couch, Warwick, Dean, Robert, De Silva, Gayandhi, Gers, L, Freeman, Kenneth, Keller, Stefan, Wylie de Boer, Elizabeth, Sheinis, Andrew, Barden, Sam, Birchall, Michael, Carollo, Daniela, Bland-Hawthorn, Joss, Brzeski, Jurek, Case, S, Cannon, R. D., Churilov, Vladimir, Couch, Warwick, Dean, Robert, De Silva, Gayandhi, Gers, L, Freeman, Kenneth, Keller, Stefan, and Wylie de Boer, Elizabeth

Abstract

The High Efficiency and Resolution Multi Element Spectrograph, HERMES is an facility-class optical spectrograph for the AAT. It is designed primarily for Galactic Archeology [21], the first major attempt to create a detailed understanding of galaxy formation and evolution by studying the history of our own galaxy, the Milky Way. The goal of the GALAH survey is to reconstruct the mass assembly history of the of the Milky Way, through a detailed spatially tagged abundance study of one million stars. The spectrograph is based at the Anglo Australian Telescope (AAT) and is fed by the existing 2dF robotic fiber positioning system. The spectrograph uses VPH-gratings to achieve a spectral resolving power of 28,000 in standard mode and also provides a high-resolution mode ranging between 40,000 to 50,000 using a slit mask. The GALAH survey requires a SNR greater than 100 for a star brightness of V=14. The total spectral coverage of the four channels is about 100nm between 370 and 1000nm for up to 392 simultaneous targets within the 2 degree field of view. Hermes has been commissioned over 3 runs, during bright time in October, November and December 2013, in parallel with the beginning of the GALAH Pilot survey starting in November 2013. In this paper we present the first-light results from the commissioning run and the beginning of the GALAH Survey, including performance results such as throughput and resolution, as well as instrument reliability. We compare the abundance calculations from the pilot survey to those in the literature.

Published
2014

17. GNOSIS: The first instrument to use fiber bragg gratings for OH suppression

Author

Trinh, C, Ellis, S C, Bland-Hawthorn, Joss, Lawrence, J S, Horton, A J, Leon-Saval, S G, Shortridge, Keith, Bryant, J., Case, S, Colless, Matthew, Couch, Warrick, Freeman, Kenneth, Lohmannsroben, Hans-Gerd, Gers, L, Glazebrook, Karl, Haynes, Roger, Lee, Steve, O'Byrne, John, Miziarski, Stan, Roth, Martin M., Schmidt, Brian, Tinney, C. G., Zheng, Jessica, Trinh, C, Ellis, S C, Bland-Hawthorn, Joss, Lawrence, J S, Horton, A J, Leon-Saval, S G, Shortridge, Keith, Bryant, J., Case, S, Colless, Matthew, Couch, Warrick, Freeman, Kenneth, Lohmannsroben, Hans-Gerd, Gers, L, Glazebrook, Karl, Haynes, Roger, Lee, Steve, O'Byrne, John, Miziarski, Stan, Roth, Martin M., Schmidt, Brian, Tinney, C. G., and Zheng, Jessica

Abstract

The near-infrared is an important part of the spectrum in astronomy, especially in cosmology because the light from objects in the early universe is redshifted to these wavelengths. However, deep near-infrared observations are extremely difficult to make

Published
2013

18. MANIFEST instrument concept and related technologies

Author

Goodwin, Michael, Brzeski, Jurek, Case, S, Colless, Matthew, Gers, L, Heijmans, Jeroen, Lawrence, J, Miziarski, Stan, Saunders, Will, Tims, J, Waller, Lew, Gilbert, James, Lawrence, J S, Muller, Rolf, Goodwin, Michael, Brzeski, Jurek, Case, S, Colless, Matthew, Gers, L, Heijmans, Jeroen, Lawrence, J, Miziarski, Stan, Saunders, Will, Tims, J, Waller, Lew, Gilbert, James, Lawrence, J S, and Muller, Rolf

Abstract

The Australian Astronomical Observatory (AAO) has recently completed a feasibility study for a fiber-positioner facility proposed for the Giant Magellan Telescope (GMT), called MANIFEST (the Many Instrument Fiber System). The MANIFEST facility takes full

Published
2012

19. Integrating the HERMES spectrograph for the AAT

Author

Heijmans, Jeroen, Asplund, Martin, Barden, Sam, Birchall, Michael, Carollo, Daniela, Bland-Hawthorn, Joss, Brzeski, Jurek, Case, S, Churilov, Vladimir, Colless, Matthew, Dean, Robert, De Silva, Gayandhi, Freeman, Kenneth, Wylie de Boer, Elizabeth, Gers, L, Lawrence, J, Lawrence, J S, Lee, Steve, Miziarski, Stan, Muller, Rolf, Shortridge, Keith, Staszak, N, Heijmans, Jeroen, Asplund, Martin, Barden, Sam, Birchall, Michael, Carollo, Daniela, Bland-Hawthorn, Joss, Brzeski, Jurek, Case, S, Churilov, Vladimir, Colless, Matthew, Dean, Robert, De Silva, Gayandhi, Freeman, Kenneth, Wylie de Boer, Elizabeth, Gers, L, Lawrence, J, Lawrence, J S, Lee, Steve, Miziarski, Stan, Muller, Rolf, Shortridge, Keith, and Staszak, N

Abstract

The High Efficiency and Resolution Multi Element Spectrograph, HERMES is an optical spectrograph designed primarily for the GALAH, Galactic Archeology Survey, the first major attempt to create a detailed understanding of galaxy formation and evolution by

Published
2012

20. Hector: A high-multiplex survey instrument for spatially-resolved galaxy spectroscopy

Author

Lawrence, J, Bland-Hawthorn, Joss, Bryant, J., Brzeski, Jurek, Colless, Matthew, Croom, Scott M, Gers, L, Gilbert, James, Gillingham, Peter, Heijmans, Jeroen, Horton, A J, Miziarski, Stan, Ireland, Michael, Lawrence, J, Bland-Hawthorn, Joss, Bryant, J., Brzeski, Jurek, Colless, Matthew, Croom, Scott M, Gers, L, Gilbert, James, Gillingham, Peter, Heijmans, Jeroen, Horton, A J, Miziarski, Stan, and Ireland, Michael

Abstract

First light from the SAMI (Sydney-AAO Multi-object IFS) instrument at the Anglo-Australian Telescope (AAT) has recently proven the viability of fibre hexabundles for multi-IFU spectroscopy. SAMI, which comprises 13 hexabundle IFUs deployable over a 1 degree field-of-view, has recently begun science observations, and will target a survey of several thousand galaxies. The scientific outputs from such galaxy surveys are strongly linked to survey size, leading the push towards instruments with higher multiplex capability. We have begun work on a new instrument concept, called Hector, which will target a spatially-resolved spectroscopic survey of up to one hundred thousand galaxies. The key science questions for this instrument concept include how do galaxies get their gas, how is star formation and nuclear activity affected by environment, what is the role of feedback, and what processes can be linked to galaxy groups and clusters. One design option for Hector uses the existing 2 degree field-of view top end at the AAT, with 50 individual robotically deployable 61-core hexabundle IFUs, and 3 fixed format spectrographs covering the visible wavelength range with a spectral resolution of approximately 4000. A more ambitious option incorporates a modified top end at the AAT with a new 3 degree field-of-view wide-field-corrector and 100 hexabundle IFUs feeding 6 spectrographs.

Published
2012

21. GNOSIS: a novel near-infrared OH suppression unit at the AAT

Author

Trinh, C. Q., primary, Ellis, S. C., additional, Lawrence, J. S., additional, Horton, A. J., additional, Bland-Hawthorn, J., additional, Leon-Saval, S. G., additional, Bryant, J., additional, Case, S., additional, Colless, M., additional, Couch, W., additional, Freeman, K., additional, Gers, L., additional, Glazebrook, K., additional, Haynes, R., additional, Lee, S., additional, Löhmannsröben, H.-G., additional, Miziarski, S., additional, O'Byrne, J., additional, Rambold, W., additional, Roth, M. M., additional, Schmidt, B., additional, Shortridge, K., additional, Smedley, S., additional, Tinney, C. G., additional, Xavier, P., additional, and Zheng, J., additional

Published
2012
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22. Suppression of the near-infrared OH night-sky lines with fibre Bragg gratings - first results

Author

Ellis, S. C., primary, Bland-Hawthorn, J., additional, Lawrence, J., additional, Horton, A. J., additional, Trinh, C., additional, Leon-Saval, S. G., additional, Shortridge, K., additional, Bryant, J., additional, Case, S., additional, Colless, M., additional, Couch, W., additional, Freeman, K., additional, Gers, L., additional, Glazebrook, K., additional, Haynes, R., additional, Lee, S., additional, Löhmannsröben, H.-G., additional, O'Byrne, J., additional, Miziarski, S., additional, Roth, M., additional, Schmidt, B., additional, Tinney, C. G., additional, and Zheng, J., additional

Published
2012
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25. Atmospheric OH suppression with GNOSIS at the Anglo-Australian Telescope

Author

Lawrence, J. S., primary, Ellis, S. C., additional, Bland-Hawthorn, J., additional, Bryant, J., additional, Case, S., additional, Gers, L., additional, Haynes, R., additional, Horton, A., additional, Lee, S., additional, Leon-Saval, S., additional, Loehmannsroeben, H., additional, Miziarski, S., additional, O'Byrne, J., additional, Rambold, W., additional, Roth, M., additional, Shortridge, K., additional, Smedley, S., additional, Trinh, C., additional, Xavier, P., additional, and Zheng, J., additional

Published
2011
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26. GNOSIS: An OH suppressing near-infrared spectrograph for astronomy using fibre Bragg gratings

Author

Lawrence, J. S., primary, Ellis, S.C., additional, Bland-Hawthorn, J., additional, Bryant, J., additional, Case, S., additional, Gers, L., additional, Haynes, R., additional, Horton, A., additional, Lee, S., additional, Leon-Saval, S., additional, Loehmannsroeben, H., additional, Miziarski, S., additional, Mladenoff, J., additional, O'Byrne, J., additional, Rambold, W., additional, Roth, M., additional, Smedley, S., additional, and Trinh, C., additional

Published
2011
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34. Design and development of the high-resolution spectrograph HERMES and the unique volume phase holographic gratings

Author

Heijmans, J. A. C., Gers, L., and Faught, B.

Abstract

We report on the grating development for the High Efficiency and Resolution Multi Element Spectrograph (HERMES). This paper discusses the challenges of designing, optimizing, and tolerancing large aperture volume phase holographic (VPH) gratings for HERMES. The high spectral resolution requirements require steep angles of incidence, of 67.2 degrees, and high line densities, ranging between 2400 and 3800 lines per mm, resulting in VPH gratings that are highly s-polarized that push the fabrication process to its limits.

Published
2011
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36. GNOSIS: The First Fiber Bragg Grating-based OH Suppression Unit

Author

Trinh, Christopher, Ellis, S. C., Bland-Hawthorn, J., Lawrence, J. S., Horton, A. J., Leon-Saval, S. G., Shortridge, K., Julia Bryant, Case, S., Colless, M., Couch, W., Freeman, K. C., Löhmannsröben, H., Gers, L., Glazebrook, K., Haynes, R., Lee, S., O Byrne, J., Miziarski, S., Roth, M. M., Schmidt, B., Tinney, C. G., and Zheng, J.

38. Design and development of the fibre cable and fore optics of the HERMES Spectrograph for the Anglo-Australian Telescope (AAT)

Author

Brzeski, J., Case, S., and Gers, L.

Abstract

We report on the development of the fibre slit for the High Efficiency and Resolution Multi Element Spectrograph (HERMES). This paper discusses the design, mounting and alignment techniques of 784 science fibres and the magnificatin optics divided among two slit bodies. The measured performance of the fiber bundle shows an increased throughput of 50% in the existing AAOmega spectrograph using the same fiber mounting techniques.

Published
2011
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39. Antidepressant use in older inpatients: current situation and application of the revised STOPP criteria.

Author

Gers L, Petrovic M, Perkisas S, and Vandewoude M

Abstract

Objectives: Antidepressant use increases as age rises. Moreover, older patients are more sensitive to side effects and drug interactions. This descriptive study aims to map antidepressant use among patients at the geriatrics department of a university hospital and to evaluate whether prescribing happens in an evidence-based manner., Methods: Patients aged 75 years and over, admitted to the geriatrics department of the Middelheim Hospital in Antwerp between February and July 2017 were included. We checked whether they took antidepressants, which types and doses were prescribed, who prescribed the antidepressants, and whether prescribing was in concordance with the revised STOPP (Screening Tool of Older People's Prescriptions) criteria., Results: Out of the 239 included patients, 61 were found to use antidepressants, with depression being the most important indication. General practitioners appeared to be the most frequent prescribers. Trazodone was the most prescribed antidepressant and was often used for sleeping disorders. Antidepressants were taken longer than recommended in almost one out of five cases. Patients with diabetes and renal insufficiency were prescribed antidepressants less frequently. Only 2.8% of the study participants were prescribed antidepressants for anxiety disorders., Conclusion: We can conclude that prescription of antidepressants in older patients at the geriatrics department is often not evidence based. Clear guidelines may offer a solution; therefore more studies are needed on antidepressant use in older patients., Competing Interests: Conflict of interest statement: The authors declare that there is no conflict of interest.

Published
2018
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