We obtained optical spectra of the afterglow of GRB 090424 (Cannizzo et al., GCN 9223) using GMOS on Gemini-South. Our spectra cover the wavelength range of 4400-8600 angstroms. Our first 1200s exposure, starting at 01:51:56 April 25 UT (11.7 hr after the trigger) reveals.a pair of absorption lines at 6077 and 6130 Angs, which we identify as the Ca II H+K doublet at z=0.544. Additionally, an emission...Full Text

We initiated a series of 15 x 200 second exposures of the field of GRB 090423 (Krimm et al, GCN 9198) in z-band using GMOS on Gemini-South starting at 23:38 UT on 2009-04-23, 15.71 hours after the trigger. No source is visible in the XRT error circle (Evans et al., GCN 9205) or the NIR position (Tanvir et al., GCN 9202) in the co-added image. We estimate a limiting magnitude (3-sigma) of: z...Full Text

We have obtained optical spectra of the candidate UVOT afterglow (GCN 9046, 9048) of the Fermi GRB 090328 (GCN 9044) with the Gemini Multi-Object Spectrograph mounted on the Gemini South Telescope. Observations began at 00:05 UT on 2009 March 29. Our first 1500 second spectrum uses the R400 grating and covers the approximate wavelength range from 4000-8000 A. We find a single bright emission...Full Text

We performed spectroscopy on the afterglow of GRB 090323 (Ohno et al., GCN 9021; Updike et al., GCN 9026; Cenko and Perley, GCN 9027) using Gemini-South (GMOS) starting at 05:58 UT on 2009-03-24, approximately 30 hours after the trigger. We conducted a series of four exposures of 600 seconds, two using the B600 grating centered at 6000 Angstroms and two with the R400 grating centered at 8000 Angstroms...Full Text

We have imaged the field of GRB 090308 (Evans et al.; GCN 8948) with GMOS mounted on the Gemini South telescope beginning at approximately 1:38 UT on the night of 9 MarcHETE 2009 (~ 7.6 hours after the burst). Images were taken in the g', r', i', and z' filters for a total of 300 s in each band. We find no significant sources inside the revised XRT error circle (Evans et al.; GCN 8956) to the...Full Text

We have imaged the field of the short GRB 090305 (Beardmore et al., GCN 8932) with GMOS mounted on the Gemini South telescope beginning approximately 27 minutes after the burst. Observations were taken in the Sloan g', r', and i' filters and cover nearly the entire BAT error circle. Inside the BAT error circle, we find a fading point source at the location (J2000.0): RA: 16:07:07.61 Dec...Full Text

D. A. Kann, TLS Tautenburg, report:...Full Text

The robotic 0.8-m KAIT located at Lick Observatory responded to GRB 080727B (Immler et al. GCN 8022) automatically on July 27 starting at 08:14:12 UT (48 seconds after the burst). A series of images were taken in the V, I, and clear filters. We detected a fading new object at the following location: ...Full Text

Starting at09:25 UT on 2008 July 10 we began spectroscopy of the optical counterpart (Li et al., GCN 7959) of GRB 080710 (Sbarufatti et al., GCN 7957) using Gemini-South (+GMOS). We acquired 2x1200s integrations using the B600 grism, covering a wavelength range from 3800 to 6700 Angstroms. ...Full Text

GRB 070809 was a short-hard burst (Barthelmy et al., GCN 6788) detected by Swift. In our observations on 2007-08-10 and 2007-08-11 we detected a very faint optical afterglow candidate and presented evidence (at about the 3-sigma level) for fading between the two nights. (GCN 6739, GCN 6774)....Full Text

On the night of 2008-06-07 (UT) we observed the location of the Super-AGILE burst GRB 080514B (GCN 7715, Rapisarda et al.) with Keck I / LRIS in g and R filters for 1080s and 960s respectively, starting at 12:53 UT. We detect a source consistent with the afterglow position (de Ugarte Postigo et al., GCN 7719) in both filters. Photometry within a 1.1" radius aperture gives an magnitude...Full Text

On the night of 2008-06-07 (UT) we re-observed the location of GRB 080603A (GCN 7790, Paizis et al.) with Keck I / LRIS in g and R filters for 785s and 690s respectively, starting at 12:30 UT. The optical afterglow (Gomboc et al., GCN 7788; Chornock et al., GCN 7789) is well-detected as the northern member of a complex of sources. Calibrating relative to four nearby USNO B1.0 stars we...Full Text

We observed the optical afterglow of GRB 080607 (Mangano et al., GCN 7847, Rujopakarn et al., GCN 7846) with the 1.3m Peters Automated Infrared Imaging Telescope (PAIRITEL). Observations began at 06:08:44 Jun 07, 2008 UT. We detect the afterglow in a 612 sec mosaic of 7.8 sec simultaneous exposures in the J, H, and Ks filters. Preliminary photometry for the afterglow in exposures beginning...Full Text

Upon receiving the GCN alert we immediately slewed with Keck I (+LRIS) to the field of GRB 080607 (GCN 7847, Mangano et al.). The optical transient (GCN 7846, Rujopakarn et al.) was visually identified on the guider. Spectroscopic observations began at 06:20:35 UT, 13 minutes after the trigger, using the 600 and 400 line gratings on the blue and red cameras, respectively, for wavelength...Full Text

We observed the optical afterglow of GRB 080603B (Mangano et al., GCN 7794) with the 1.3m Peters Automated Infrared Imaging Telescope (PAIRITEL) starting 7.66 hours post trigger on June 04, 2008 UT. We detected the afterglow in a 2291 sec mosiac of 7.8 sec simultaneous exposures in the J, H, and Ks filters. Preliminary photometry for the afterglow in exposures beginning on Jun 04.14 UT...Full Text

We observed the optical afterglow of GRB 080603A (Paizis et al., GCN 7790; Gomboc et al., GCN 7788; Chornock et al; GCN 7789) with the 1.3m Peters Automated Infrared Imaging Telescope (PAIRITEL) starting 18.89 hours post trigger on June 04, 2008 UT. We detected the afterglow in a 2927 sec mosaic of simultaneous 7.8 sec exposures in the J, H, and Ks filters. Preliminary photometry for the...Full Text

Following the KAIT detection (Chornock et al., GCN 7789) of the afterglow candidate of GRB 080603 (Paizis et al., GCN 7790; Gomboc et al., GCN 7788) we began a spectroscopic sequence at Gemini-North using GMOS. We acquired 2x1200s longslit exposures starting at UT 13:24. We detect very strong resonance lines of MgII and FeII and the fine-structure transitions of FeII which establish...Full Text

From 2008/05/25 18:11:36 UT to 2008/05/26 03:04:28 UT (22.24 - 22.61 days post burst), Chandra Director's Discretionary Time observations with ACIS-S were conducted of the field of GRB 080503 (e.g., Mao et al. 2008; GCN 7665) for a total exposure of 29.8 ksec (livetime). In a 3-pixel radius source extraction region centered around the first epoch Chandra source (Butler et al. 2008; GCN 7704)...Full Text

Further to GCN 7703 (Bloom et al.), we obtained additional imaging using the Hubble Space Telescope (+WFPC2) of GRB 080503 (Mao et al., GCN 7665) starting at 15:05:05 on UT 2008-05-12, about 9.2 days after the trigger. Four exposures of 1000s each were acquired in F606W and in F814W. ...Full Text

The optical afterglow of long-duration gamma-ray burst GRB 071003 is among the brightest yet to be detected from any GRB, with R ~ 12 mag in Katzman Automatic Imaging Telescope observations starting 42 s after the GRB trigger, including filtered detections during prompt emission. However, our high signal-to-noise ratio afterglow spectrum displays only extremely weak absorption lines at what we argue...Full Text