An absolute calibration of DENIS (deep near infrared southern sky survey)

¹ DESPA, Observatoire de Paris, 5 place J. Janssen, F-92195 Meudon Cedex, France
² European Southern Observatory, Casilla 19001, Santiago 19, Chile
³ Radio Astronomy Laboratory, 601 Campbell Hall, University of California, Berkeley, CA 94720, U.S.A.
⁴ Institut d'Astrophysique de Paris, 98 bis Bd. Arago, F-75014 Paris, France
⁵ DASGAL, Observatoire de Paris, 61 Av. de l'Observatoire, F-75014 Paris, France
⁶ DASGAL, Observatoire de Paris, 5 place J. Janssen, F-92195 Meudon Cedex, France
⁷ Leiden Observatory, University of Leiden, P.O. Box 9513, 2300 RA Leiden, The Netherlands
⁸ CDS, Observatoire Astronomique de Strasbourg, UMR 7550, 11 rue de l'Université, F-67000 Strasbourg, France
⁹ CEA, DSM, DAPNIA, Centre d'Études de Saclay, F-91191 Gif-sur-Yvette Cedex, France
¹⁰ Observatoire de la Côte d'Azur, Département Fresnel, F-06304 Nice Cedex, France
¹¹ Observatoire de Grenoble, 414 rue de la Piscine, Domaine Universitaire de Saint Martin d'Hères, F-38041 Grenoble, France
¹² Instituto de Astrofísica de Canarias, E-38200 La Laguna, Tenerife, Spain
¹³ Institut für Astronomie der Universität Wien, Türkenschanzstrasse 17, A-1180 Wien, Austria
¹⁴ Institut für Astronomie, Innsbruck University, A-6020 Innsbruck, Austria
¹⁵ DEMIRM, Observatoire de Paris, 61 Av. de l'Observatoire, F-75014 Paris, France
¹⁶ DAEC, Observatoire de Paris, 5 place J. Janssen, F-92195 Meudon Cedex, France
¹⁷ CRAL, Observatoire de Lyon, F-69561 Saint-Genis Laval Cedex, France
¹⁸ Istituto di Astrofisica Spaziale, CNR, C.P. 67, I-00044 Frascati, Italy
¹⁹ Observatoire de Besançon, BP. 1615, F-25010 Besançon Cedex, France
²⁰ Landessternwarte Heidelberg, Königstuhl, D-69117 Heidelberg, Germany

Send offprint request to: P. Fouqué

Received: 24 June 1999
Accepted: 20 October 1999

Abstract


An absolute calibration of the DENIS photometric system is presented. It includes the determination of the overall transmission profiles in the 3 bands, namely i, J and K_s, combining contributions from atmosphere, telescope mirrors, instrument lenses and dichroics, filters, and detectors. From these normalized profiles, isophotal and effective wavelengths are computed, using the same synthetic Vega spectrum as that used to support the absolute calibration of many other ground-based and spaceborne photometric systems. Flux densities at zero magnitude are derived and integrated to give in-band fluxes, which are used to compute theoretical zero-points and compare them to observed ones, yielding estimates of the overall throughput of the whole system.