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Title: COSMOGRAIL: XVII. Time delays for the quadruply imaged quasar PG 1115+080

Abstract

Here, we present time-delay estimates for the quadruply imaged quasar PG 1115+080. Our results are based on almost daily observations for seven months at the ESO MPIA 2.2m telescope at La Silla Observatory, reaching a signal-to-noise ratio of about 1000 per quasar image. In addition, we re-analyze existing light curves from the literature that we complete with an additional three seasons of monitoring with the Mercator telescope at La Palma Observatory. When exploring the possible source of bias we consider the so-called microlensing time delay, a potential source of systematic error so far never directly accounted for in previous time-delay publications. In fifteen years of data on PG 1115+080, we find no strong evidence of microlensing time delay. Therefore not accounting for this effect, our time-delay estimates on the individual data sets are in good agreement with each other and with the literature. Combining the data sets, we obtain the most precise time-delay estimates to date on PG 1115+080, with Δt(AB) = 8.3 +1.5 –1.6 days (18.7% precision), Δt(AC) = 9.9 +1.1 –1.1 days (11.1%) and Δt(BC) = 18.8 +1.6 –1.6 days (8.5%). Turning these time delays into cosmological constraints is done in a companion paper that makes use ofmore » ground-based Adaptive Optics (AO) with the Keck telescope.« less

Authors:
ORCiD logo [1];  [1];  [1];  [2];  [1];  [3];  [3];  [1];  [4];  [5];  [6];  [7];  [8];  [7];  [9];  [10];  [8];  [11];  [7];  [6] more »;  [12];  [12];  [12];  [13];  [1];  [2];  [14] « less
  1. Ecole Polytechnique Federale de Lausanne (EPFL), Versoix (Switzerland)
  2. Univ. de Valparaiso, Valparaiso (Chile)
  3. Univ. of California, Davis, CA (United States)
  4. Argelander-Institut fur Astronomie, Bonn (Germany)
  5. Max-Planck-Institute for Astrophysics, Garching (Germany)
  6. Univ. Andres Bello Fernandez Concha, Santiago (Chile)
  7. Univ. of California, Los Angeles, CA (United States)
  8. Stanford Univ., Stanford, CA (United States)
  9. Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
  10. Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Univ. of Chicago, Chicago, IL (United States)
  11. Max-Planck-Institute for Astrophysics, Garching (Germany); Technische Univ. Munchen, Garching (Germany); Academia Sinica, Taipei (Taiwan)
  12. Pontificia Univ. Catolica de Chile, Santiago (Chile); Max-Planck-Institut fur Astronomie, Heidelberg (Germany)
  13. Univ. Andres Bello Fernandez Concha, Santiago (Chile); Millennium Institute of Astrophysics (Chile)
  14. Univ. de Liege, Liege (Belgium)
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
OSTI Identifier:
1439464
Report Number(s):
arXiv:1804.09183; FERMILAB-PUB-18-151-A-AE
Journal ID: ISSN 0004-6361; 1670070; TRN: US1900617
Grant/Contract Number:  
AC02-07CH11359
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Astronomy and Astrophysics
Additional Journal Information:
Journal Volume: 616; Journal ID: ISSN 0004-6361
Publisher:
EDP Sciences
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; methods: data analysis; gravitational lensing: strong; cosmological parameters

Citation Formats

Bonvin, Vivien, Chan, J. H. H., Millon, M., Rojas, K., Courbin, F., Chen, G. C. -F., Fassnacht, C. D., Paic, E., Tewes, M., Chao, D. C. -Y., Chijani, M., Gilman, D., Gilmore, K., Williams, P., Buckley-Geer, E., Frieman, J., Marshall, P. J., Suyu, S. H., Treu, T., Hempel, A., Kim, S., Lachaume, R., Rabus, M., Anguita, T., Meylan, G., Motta, V., and Magain, P. COSMOGRAIL: XVII. Time delays for the quadruply imaged quasar PG 1115+080. United States: N. p., 2018. Web. doi:10.1051/0004-6361/201833287.
Bonvin, Vivien, Chan, J. H. H., Millon, M., Rojas, K., Courbin, F., Chen, G. C. -F., Fassnacht, C. D., Paic, E., Tewes, M., Chao, D. C. -Y., Chijani, M., Gilman, D., Gilmore, K., Williams, P., Buckley-Geer, E., Frieman, J., Marshall, P. J., Suyu, S. H., Treu, T., Hempel, A., Kim, S., Lachaume, R., Rabus, M., Anguita, T., Meylan, G., Motta, V., & Magain, P. COSMOGRAIL: XVII. Time delays for the quadruply imaged quasar PG 1115+080. United States. doi:10.1051/0004-6361/201833287.
Bonvin, Vivien, Chan, J. H. H., Millon, M., Rojas, K., Courbin, F., Chen, G. C. -F., Fassnacht, C. D., Paic, E., Tewes, M., Chao, D. C. -Y., Chijani, M., Gilman, D., Gilmore, K., Williams, P., Buckley-Geer, E., Frieman, J., Marshall, P. J., Suyu, S. H., Treu, T., Hempel, A., Kim, S., Lachaume, R., Rabus, M., Anguita, T., Meylan, G., Motta, V., and Magain, P. Tue . "COSMOGRAIL: XVII. Time delays for the quadruply imaged quasar PG 1115+080". United States. doi:10.1051/0004-6361/201833287. https://www.osti.gov/servlets/purl/1439464.
@article{osti_1439464,
title = {COSMOGRAIL: XVII. Time delays for the quadruply imaged quasar PG 1115+080},
author = {Bonvin, Vivien and Chan, J. H. H. and Millon, M. and Rojas, K. and Courbin, F. and Chen, G. C. -F. and Fassnacht, C. D. and Paic, E. and Tewes, M. and Chao, D. C. -Y. and Chijani, M. and Gilman, D. and Gilmore, K. and Williams, P. and Buckley-Geer, E. and Frieman, J. and Marshall, P. J. and Suyu, S. H. and Treu, T. and Hempel, A. and Kim, S. and Lachaume, R. and Rabus, M. and Anguita, T. and Meylan, G. and Motta, V. and Magain, P.},
abstractNote = {Here, we present time-delay estimates for the quadruply imaged quasar PG 1115+080. Our results are based on almost daily observations for seven months at the ESO MPIA 2.2m telescope at La Silla Observatory, reaching a signal-to-noise ratio of about 1000 per quasar image. In addition, we re-analyze existing light curves from the literature that we complete with an additional three seasons of monitoring with the Mercator telescope at La Palma Observatory. When exploring the possible source of bias we consider the so-called microlensing time delay, a potential source of systematic error so far never directly accounted for in previous time-delay publications. In fifteen years of data on PG 1115+080, we find no strong evidence of microlensing time delay. Therefore not accounting for this effect, our time-delay estimates on the individual data sets are in good agreement with each other and with the literature. Combining the data sets, we obtain the most precise time-delay estimates to date on PG 1115+080, with Δt(AB) = 8.3+1.5–1.6 days (18.7% precision), Δt(AC) = 9.9+1.1–1.1 days (11.1%) and Δt(BC) = 18.8+1.6–1.6 days (8.5%). Turning these time delays into cosmological constraints is done in a companion paper that makes use of ground-based Adaptive Optics (AO) with the Keck telescope.},
doi = {10.1051/0004-6361/201833287},
journal = {Astronomy and Astrophysics},
issn = {0004-6361},
number = ,
volume = 616,
place = {United States},
year = {2018},
month = {9}
}

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