LOTIS, Super-LOTIS, Sloan Digital Sky Survey, and Tautenburg Observations of GRB 010921 H
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Clemson University TigerPrints Publications Physics and Astronomy Summer 6-1-2002 LOTIS, Super-LOTIS, Sloan Digital Sky Survey, and Tautenburg Observations of GRB 010921 H. S. Park Lawrence Livermore National Laboratory G. G. Williams Steward Observatory, University of Arizona Dieter H. Hartmann Department of Physics and Astronomy, Clemson University, [email protected] D. Q. Lamb Department of Astronomy and Astrophysics, University of Chicago & Enrico Fermi Institute, University of Chicago B. C. Lee Experimental Astrophysics Group, Fermi National Accelerator Laboratory See next page for additional authors Follow this and additional works at: https://tigerprints.clemson.edu/physastro_pubs Recommended Citation Please use publisher's recommended citation. This Article is brought to you for free and open access by the Physics and Astronomy at TigerPrints. It has been accepted for inclusion in Publications by an authorized administrator of TigerPrints. For more information, please contact [email protected]. Authors H. S. Park, G. G. Williams, Dieter H. Hartmann, D. Q. Lamb, B. C. Lee, D. L. Tucker, S. Klose, B. Stecklum, A. Henden, and J. Adelman This article is available at TigerPrints: https://tigerprints.clemson.edu/physastro_pubs/25 The Astrophysical Journal, 571:L131–L135, 2002 June 1 ᭧ 2002. The American Astronomical Society. All rights reserved. Printed in U.S.A. LOTIS, SUPER-LOTIS, SLOAN DIGITAL SKY SURVEY, AND TAUTENBURG OBSERVATIONS OF GRB 010921 H. S. Park,1 G. G. Williams,2 D. H. Hartmann,3 D. Q. Lamb,4,5 B. C. Lee,6 D. L. Tucker,6 S. Klose,7 B. Stecklum,7 A. Henden,8 J. Adelman,6 S. D. Barthelmy,9 J. W. Briggs,10 J. Brinkmann,11 B. Chen,12,13 T. Cline,9 I. Csabai,12,14 N. Gehrels,9 M. Harvanek,11 G. S. Hennessy,15 K. Hurley,16 Zˇ eljko Ivezic´,17 S. Kent,6 S. J. Kleinman,11 J. Krzesinski,11,18 K. Lindsay,3 D. Long,11 R. Nemiroff,19 E. H. Neilsen,6 A. Nitta,11 H. J. Newberg,20 P. R. Newman,11 D. Perez,19 W. Periera,19 D. P. Schneider,21 S. A. Snedden,11 C. Stoughton,6 D. E. Vanden Berk,6 D. York,4,5 and K. Ziock1 Received 2002 January 1; accepted 2002 April 19; published 2002 May 9 ABSTRACT We present multi-instrument optical observations of the High Energy Transient Explorer (HETE-2) and In- terplanetary Network error box of GRB 010921. This event was the first gamma-ray burst (GRB) partly localized by HETE-2 that has resulted in the detection of an optical afterglow. In this Letter, we report the earliest known observations of the GRB 010921 field, taken with the 0.11 m Livermore Optical Transient Imaging System (LOTIS) telescope, and the earliest known detection of the GRB 010921 optical afterglow, using the 0.5 m Sloan Digital Sky Survey Photometric Telescope (SDSS PT). Observations with the LOTIS telescope began during a routine sky patrol 52 minutes after the burst. Observations were made with the SDSS PT, the 0.6 m Super-LOTIS telescope, and the 1.34 m Tautenburg Schmidt telescope 21.3, 21.8, and 37.5 hr, respectively, after the GRB. In addition, the host galaxy was observed with the US Naval Observatory Flagstaff Station 1.0 m telescope 56 days after the burst. We find that at later times (t 1 1 day after the burst), the optical afterglow exhibited a power-law However, our earliest observations show that this power-law decline . 0.28 ע decline with a slope ofa p 1.75 cannot have extended to early times (t ! 0.035 days). Subject heading: gamma rays: bursts 1 Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA 94550. 1. INTRODUCTION 2 Steward Observatory, University of Arizona, 933 North Cherry Avenue, The High Energy Transient Explorer (HETE-2)22 is currently Tucson, AZ 85721. 3 Department of Physics and Astronomy, Clemson University, 118 Kinard the only gamma-ray burst (GRB) detector capable of localizing Laboratory, Clemson, SC 29634-0978. and disseminating GRB coordinates in near real time. Low- 4 Department of Astronomy and Astrophysics, University of Chicago, 5640 energy emission during and shortly after a GRB (t Շ 1 hr) po- South Ellis Avenue, Chicago, IL 60637. tentially holds the key to understanding the central engine of 5 Enrico Fermi Institute, University of Chicago, 5640 South Ellis Avenue, GRBs and could provide clues to their progenitors (Me´sza´ros Chicago, IL 60637. 6 Experimental Astrophysics Group, Fermi National Accelerator Laboratory, 2001). P.O. Box 500, Batavia, IL 60510. The HETE-2 detection of GRB 010921 together with data 7 Thu¨ringer Landessternwarte Tautenburg, Karl-Schwarzschild-Observaorium, from the Interplanetary Network (IPN) provided the localization Sternwarte 5, 07778 Tautenburg, Germany. that resulted in the detection of an optical afterglow. Although 8 Universities Space Research Association/US Naval Observatory, Flagstaff Station, P.O. Box 1149, Flagstaff, AZ 86002-1149. the afterglow was relatively bright, early observations of the error 9 NASA Goddard Space Flight Center, Greenbelt, MD 20771. box failed to reveal any candidate afterglows because of source 10 Yerkes Observatory, University of Chicago, 373 West Geneva Street, confusion with its bright host galaxy (R ∼ 21.7 ; Price et al. 2001). Williams Bay, WI 53191. Spectroscopy of the host galaxy performed with the Palomar 11 Apache Point Observatory, P.O. Box 59, Sunspot, NM 88349-0059. 12 200 inch telescope 4 weeks after the burst indicates a redshift ע Department of Physics and Astronomy, Johns Hopkins University, 3701 p San Martin Drive, Baltimore, MD 21218. ofz 0.450 0.005 (Djorgovski et al. 2001). 13 XMM Science Operation Center, European Space Agency–Vilspa, Villa- franca del Castillo, Apartado 50727-28080 Madrid, Spain. 2. OBSERVATIONS 14 Department of Physics of Complex Systems, Eo¨tvo¨s University, Pa´zma´ny Pe´ter Se´ta´ny 1, H-1518 Budapest, Hungary. 2.1. GRB Observations by HETE-2 and IPN 15 US Naval Observatory, 3450 Massachusetts Avenue, NW, Washington, DC 20392-5420. On 2001 September 21 at 05:15:50.56 UT (September 16 Space Sciences Laboratory, University of California at Berkeley, 601 21.21934 UT), the French Gamma Telescope instrument detected Campbell Hall, Berkeley, CA 94720. a bright GRB (Trigger 1761). GRB 010921 had a duration of 17 Princeton University Observatory, Peyton Hall, Princeton, NJ 08544-1001. ∼ 1 # Ϫ7 18 12 s in the 8–85 keV band, a peak flux ofFp 3 10 ergs Mount Suhora Observatory, Cracow Pedagogical University, ul. Pod- Ϫ2 Ϫ1 ∼ # Ϫ6 Ϫ2 chorazych 2, 30-084 Cracow, Poland. cm s , and a fluence ofS 1 10 ergs cm (Ricker et 19 Department of Physics, Michigan Technological University, 1400 Town- send Drive, Houghton, MI 49931. 21 Department of Astronomy and Astrophysics, Pennsylvania State Univer- 20 Department of Physics, Rensselaer Polytechnic Institute, SC1C25, Troy, sity, 525 Davey Laboratory, University Park, PA 16802. NY 12180. 22 See http://space.mit.edu/HETE. L131 L132 OBSERVATIONS OF GRB 010921 Vol. 571 p al. 2001). For a spatially flat FRW cosmology (Qm 0.3 , 2.4. Super-LOTIS Observations p 0.7, andH p 65 km sϪ1 MpcϪ1), the measured redshift QL 0 The center of the IPN error box for GRB 010921 was added implies an equivalent isotropic energy release of6 # 10 50 ergs. to the Super-LOTIS sky patrol table, and observations of the We compare this energy with the standard energy reservoir, location began shortly after nightfall on September 22.128 UT. E ∼ 5 # 10 50 ergs, suggested by Frail et al. (2001) in the 0 Super-LOTIS is an f/3.5, 0.6 m Boller & Chivens telescope 20–2000 keV range by multiplying by the flux ratio located at Kitt Peak (near Tucson, Arizona). Its focal plane F /F of 3–10, estimated utilizing average values 20–2000 keV 8–20 keV array is a Loral2048 # 2048 CCD camera covering a 51 # ofp Ϫ1 ,p Ϫ2.2 , andE p 220 keV for the Band func- a b peak 51 FOV. The system is fully automated and capable of re- tion (Preece et al. 2000). Thus, the inferred energy of (3– sponding to a real-time GRB trigger within ∼30 s. A total of 10) # 6 # 10 50 ergs is consistent with a standard gamma-ray 20 50 s exposures were obtained during the first epoch. Super- jet with modest opening angle (Ricker et al. 2001, 2002; Price LOTIS reobserved the field on September 22 and 23 UT be- et al. 2002b). ginning at 22.267, 23.128, and 23.269 UT. Each of these (no The burst was also detected in the Wide-field X-ray Monitor filter) observations also consisted of 20 50 s exposures. (WXM) X-detector but was outside the field of view (FOV) of the WXM Y-detector. Because the GRB was not well localized 2.5. Tautenburg Observations in the Y-direction, a location was not distributed with the real- time trigger. Approximately 5 hr after the GRB, ground analysis On September 22.781, the Tautenburg Schmidt telescope be- ∼ Њ # ∼ Ј gave a long narrow error box ( 10 20 ) centered at gan observations of the error box in the IC band. This telescope, a, d p 23hm 2 14.6 s,44Њ16Ј4Љ.8 (J2000.0; Ricker et al. 2001). located at Tautenburg, Germany, is an f/2, 1.34 m aperture tele- Ulysses and BeppoSAX also detected GRB 010921. These de- scope equipped with a SITe2048 # 2048 CCD as the focal tections resulted (∼15 hr after the burst) in an IPN annulus plane array. Its FOV is36 # 36 . Thirty-eight 120 s exposures centered ata, d p 15hms 29 11.8 , 67Њ36Ј18Љ.0 (J2000.0), with ra- were acquired.