Identifying high-redshift gamma-ray bursts with RATIR

O. M. Littlejohns, Nathaniel Butler, A. Cucchiara, A. M. Watson, A. S. Kutyrev, W. H. Lee, M. G. Richer, C. R. Klein, O. D. Fox, J. X. Prochaska, J. S. Bloom, E. Troja, E. Ramirez-Ruiz, J. A. De Diego, L. Georgiev, J. González, C. G. Román-Zúñiga, N. Gehrels, H. Moseley

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

We present a template-fitting algorithm for determining photometric redshifts, zphot, of candidate high-redshift gamma-ray bursts (GRBs). Using afterglow photometry, obtained by the Reionization and Transients InfraRed (RATIR) camera, this algorithm accounts for the intrinsic GRB afterglow spectral energy distribution, host dust extinction, and the effect of neutral hydrogen (local and cosmological) along the line of sight. We present the results obtained by this algorithm and the RATIR photometry of GRB 130606A, finding a range of best-fit solutions, 5.6 < zphot < 6.0, for models of several host dust extinction laws (none, the Milky Way, Large Magellanic Clouds, and Small Magellanic Clouds), consistent with spectroscopic measurements of the redshift of this GRB. Using simulated RATIR photometry, we find that our algorithm provides precise measures of zphot in the ranges of 4 < zphot ≲ 8 and 9 < zphot < 10 and can robustly determine when zphot > 4. Further testing highlights the required caution in cases of highly dust-extincted host galaxies. These tests also show that our algorithm does not erroneously find z phot < 4 when zsim > 4, thereby minimizing false negatives and allowing us to rapidly identify all potential high-redshift events.

Original languageEnglish (US)
Article number2
JournalAstronomical Journal
Volume148
Issue number1
DOIs
StatePublished - 2014

Fingerprint

gamma ray bursts
afterglows
dust
infrared photometry
spectral energy distribution
line of sight
photometry
extinction
templates
cameras
hydrogen
galaxies
energy

Keywords

  • gamma-ray burst: general
  • gamma-ray burst: individual (GRB 130606A)
  • techniques: photometric Online-only material: color figures

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Littlejohns, O. M., Butler, N., Cucchiara, A., Watson, A. M., Kutyrev, A. S., Lee, W. H., ... Moseley, H. (2014). Identifying high-redshift gamma-ray bursts with RATIR. Astronomical Journal, 148(1), [2]. https://doi.org/10.1088/0004-6256/148/1/2

Identifying high-redshift gamma-ray bursts with RATIR. / Littlejohns, O. M.; Butler, Nathaniel; Cucchiara, A.; Watson, A. M.; Kutyrev, A. S.; Lee, W. H.; Richer, M. G.; Klein, C. R.; Fox, O. D.; Prochaska, J. X.; Bloom, J. S.; Troja, E.; Ramirez-Ruiz, E.; De Diego, J. A.; Georgiev, L.; González, J.; Román-Zúñiga, C. G.; Gehrels, N.; Moseley, H.

In: Astronomical Journal, Vol. 148, No. 1, 2, 2014.

Research output: Contribution to journalArticle

Littlejohns, OM, Butler, N, Cucchiara, A, Watson, AM, Kutyrev, AS, Lee, WH, Richer, MG, Klein, CR, Fox, OD, Prochaska, JX, Bloom, JS, Troja, E, Ramirez-Ruiz, E, De Diego, JA, Georgiev, L, González, J, Román-Zúñiga, CG, Gehrels, N & Moseley, H 2014, 'Identifying high-redshift gamma-ray bursts with RATIR', Astronomical Journal, vol. 148, no. 1, 2. https://doi.org/10.1088/0004-6256/148/1/2
Littlejohns OM, Butler N, Cucchiara A, Watson AM, Kutyrev AS, Lee WH et al. Identifying high-redshift gamma-ray bursts with RATIR. Astronomical Journal. 2014;148(1). 2. https://doi.org/10.1088/0004-6256/148/1/2
Littlejohns, O. M. ; Butler, Nathaniel ; Cucchiara, A. ; Watson, A. M. ; Kutyrev, A. S. ; Lee, W. H. ; Richer, M. G. ; Klein, C. R. ; Fox, O. D. ; Prochaska, J. X. ; Bloom, J. S. ; Troja, E. ; Ramirez-Ruiz, E. ; De Diego, J. A. ; Georgiev, L. ; González, J. ; Román-Zúñiga, C. G. ; Gehrels, N. ; Moseley, H. / Identifying high-redshift gamma-ray bursts with RATIR. In: Astronomical Journal. 2014 ; Vol. 148, No. 1.
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AU - Kutyrev, A. S.

AU - Lee, W. H.

AU - Richer, M. G.

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AU - Bloom, J. S.

AU - Troja, E.

AU - Ramirez-Ruiz, E.

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