//////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3188 SUBJECT: GRB050408: MASTER optical observations DATE: 05/04/08 18:01:34 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, A.Krylov, V.Kornilov, G.Borisov, D.Kuvshinov, A.Belinski, M.Kuznetsov, S.Potanin, G.Antipov, E.Gorbovskoy, N.Tyurina Sternberg Astronomical Institute, Moscow After HETE alert 3711 MASTER robotic telescope (http://observ.pereplet.ru) had imaging the corresponding area of the sky under the bad weather conditions at 17h21m53.75 UT (1h 09m after GRB Time, OUR SUNSET ). There are no new object up to 14.7 on unfiltered image of the error box (30s exposition, 6 square degrees field). The JPG-images are available at http://observ.pereplet.ru/images/GRB050408/1.jpg This is preliminary result. Observations are continuing. This message may be cited. This work is supported by Moscow Union "Optic" and partly supported by RFFI 04-02-16411. Mailto: lipunov@sai.msu.ru //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3189 SUBJECT: GRB 050408 (=H3711): A Long X-Ray-Rich GRB Detected by HETE DATE: 05/04/08 18:23:42 GMT FROM: Don Lamb at U.Chicago GRB 050408 (=H3711): A Long X-Ray-Rich GRB Detected by HETE T. Sakamoto, G. Ricker, J-L. Atteia, N. Kawai, D. Lamb, and S. Woosley, on behalf of the HETE Science Team; M. Arimoto, T. Donaghy, E. Fenimore, M. Galassi, C. Graziani, J. Kotoku, M. Maetou, M. Matsuoka, Y. Nakagawa, R. Sato, Y. Shirasaki, M. Suzuki, T. Tamagawa, K. Tanaka, Y. Yamamoto, and A. Yoshida, on behalf of the HETE WXM Team; N. Butler, G. Crew, J. Doty, G. Prigozhin, R. Vanderspek, J. Villasenor, J. G. Jernigan, A. Levine, G. Azzibrouck, J. Braga, R. Manchanda, and G. Pizzichini, on behalf of the HETE Operations and HETE Optical-SXC Teams; M. Boer, J-F Olive, J-P Dezalay, and K. Hurley, on behalf of the HETE FREGATE Team; report: The HETE FREGATE, WXM, and SXC instruments detected GRB 050408 (=H3711) at 16:22:50.93 UT (58970.93 SOD) on 8 April 2005. WXM and SXC flight localizations were reported in a GCN Notice issued at 16:23:02, which was 11 sec after the burst trigger and while the burst was still in progress. The final WXM and SXC flight localizations were reported in a GCN Notice issued at 16:23:13 UT. The final WXM flight localization can be expressed as a circle of 14 arcminutes radius (90% confidence) that is centered at WXM-Flight: RA = 12h 01m 55s, DEC = +10d 51' 38" (J2000). The final SXC flight localization can be expressed as a circle of 150 arcseconds radius that is centered at SXC-Flight: RA = +12h 02m 15s, DEC = +10d 51' 03" (J2000). Ground analysis produced an updated SXC localization that was reported in a GCN Notice issued at 17:36:02. This ground SXC localization can be expressed as a circle of 80 arcseconds radius that is centered at SXC-Ground: RA = +12h 02m 15s, DEC = +10d 52' 01" (J2000). The burst has a duration T_90 of ~34 seconds in 7-40 keV and 7-80 keV, and T_90 of ~15 seconds in 30-400 keV. Preliminary spectral analyses show the 2-30 keV fluence of GRB 050408 to be ~1.4 x 10-6 ergs cm-2 and the 30-400 keV fluence to be ~1.9 x 10-6 ergs cm-2. Therefore GRB 050408 is an "X-ray-rich" GRB. A light curve, skymap, and spectral information for GRB 050408 are provided at the following URL: http://space.mit.edu/HETE/Bursts/GRB050408 This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3190 SUBJECT: GRB 050408: ROTSE-III Optical Limits DATE: 05/04/08 18:53:32 GMT FROM: Don Smith at U michigan GRB 050408: ROTSE-III Optical Limits D.A. Smith, S.A. Yost, & E.S. Rykoff (U of Michigan) report on behalf of the ROTSE collaboration: ROTSE-IIIa, located at Siding Spring Observatory, Australia, responded to GRB 050408 (HETE trigger 3711). An automated response produced images beginning at 16:23:09.4 UT, 18.5 s after the trigger time and 6.6 s after the alert was distributed. The first few images were therefore recorded while the burst was still active at high energies (Sakamoto et al., GCN Circ. #3189). The telescope took 10 5-sec, 10 20-sec, and a series of 60-sec eposures. These unfiltered images are calibrated relative to USNO A2.0 (R). The ROTSE-III images show strong and increasing degredation from clouds. After the 20th image (~7.7 min after the trigger time), clouds became opaque enough to render many images useless. Comparison to the DSS (second epoch) reveals no new sources within the 3-sigma SXC error circle. Individual images have limiting magnitudes ranging from 14.7-16.9. In particular, we set a limit of magnitude 14.7 in the first 5 s exposure. Coadding the first ten images yields a limiting magnitude of 15.1, and coadding the 20-s images (165.5-522.5 s after the trigger time) yields a limiting magnitude of 17.8. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3191 SUBJECT: GRB 050408: Swift XRT Position DATE: 05/04/08 19:24:18 GMT FROM: Jamie A. Kennea at PSU/Swift-XRT A. A. Wells, A. F. Abbey, J. P. Osborne, A. P. Beardmore, (U. Leicester), J. A. Kennea, M. Chester, D. N. Burrows, J. A. Nousek (PSU), M. Capalbi, F. Tamburelli (ASDC), P. Romano, C. Pagani, G. Chincarini (INAF-OAB), G. Cusumano, V. La Parola, (INAF-IASF/Palermo), D. Lamb (U. Chicago), G. Ricker (MIT) and N. Gehrels (GSFC), report on behalf of the Swift XRT team: The Swift XRT observed the field of the HETE burst GRB050408 (Sakamoto etal. 2005, GCN 3189) at 17:05:18 UT. We find a bright fading uncataloged X-ray source located at: RA(J2000) = 12:02:17.4, Dec(J2000) = +10:51:03 We estimate an uncertainty of about 6 arcseconds. This source is located 78 arcseconds from the HETE SXC-Ground position in GCN 3189. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3192 SUBJECT: GRB 050408 optical candidate DATE: 05/04/08 20:24:33 GMT FROM: Alberto Castro-Tirado at LAEFF-INTA A. de Ugarte Postigo (IAA-CSIC Granada), V. Komarova, T. Fathkullin, T. Sokolova, V. Sokolov, V. Vlasyuk, Yu. Balega (SAO RAS, Russia), S. Guziy (Univ. of Nikolaev), M. Jelinek, J. Gorosabel and A.J. Castro-Tirado (IAA-CSIC Granada), report: Following the detection by HETE-2 of the long X-ray gamma- ray burst GRB 050408 (Sakamoto et al., GCN 3189), we have taken R-band images at the 1m and 6m telescope at the Special Astrophysical observatory starting at 20.25 UT (i.e. 3.9 hr after the event). Within the X-ray error box provided by SWIFT/XRT (Wells et al. GCN 3191), we identify three point-like sources. The brightest one (R = 20.5) is at preliminary coordinates RA(2000) = 12 02 17.32, Dec(2000) = +10 51 10 (error 1"), which we identify at the potential GRB 050408 optical afterglow. The object does not appear in the corresponding DSS-2 plate. Further observations are in progress. We thanks the SAO RAS director Yu. Balega for his support for the SAO RAS GRB ToO programme. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3194 SUBJECT: GRB 050408, optical observations DATE: 05/04/08 20:56:55 GMT FROM: Sylvio Klose at TLS Tautenburg S. Klose, U. Laux, and B. Stecklum, Thuringer Landessternwarte Tautenburg, J. Greiner, MPE Garching, report: Tautenburg started observing the field of GRB 050408 (Sakamoto et al. 2005, GCN 3189) at 19:01 UT on Apr 08. Observations were performed in V, R, and I, even though the weather conditions were not good. A first inspection of the R-band images obtained between 19:29 and 19:40 UT does not show a source in the Swift/XRT error circle, implying R>20 about 3 hrs after the burst. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3195 SUBJECT: GRB 050408: opitcal observation DATE: 05/04/08 21:18:10 GMT FROM: Nobuyuki Kawai at Tokyo Tech D. Kuroda (JAXA/ISAS), K. Yanagisawa (OAO), and N. Kawai (Tokyo Tech) report on behalf of MITSUME collaboration: "We observed the field covering the entire error circle of GRB050408 (GCN 3189, Sakamoto et al.) with the 50 cm Mitsume Telescope at Okayama, Japan in V, R, and I bands from 17:49 to 18:32 (UT), and obtained 37 frames of 60 sec exposure. Comparison of the co-added image to the DSS revealed no new objects down to a limiting magnitude of R=17.8 as estimated using USNO A2.0 catalog." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3196 SUBJECT: GRB 050408: Optical afterglow confirmed DATE: 05/04/08 22:50:57 GMT FROM: Kuiyun Huang at IANCU GRB 050408: Optical afterglow confirmed K.Y. Huang, W.H. Ip, D. Kinoshita (NCU), Y. Urata, T. Tamagawa (RIKEN), Y. Qiu (BAO) and Y.Q. Lou (THCA) on behalf of the East-Asia GRB Follow-up Observation Network (EAFON)report: " We have started the observation for the field of GRB 050408 at 17:10 UT on Apr 08 (55 min after the burst). Using Lulin-One meter Telescope (LOT), we have performed 'VR broad band' filter imaging observation. These images show a source in the Swift/XRT error circle. The coordinate is consistent with that of A. de Ugarte Postigo et al. (GCN 3193). Based on our preliminary 'VR-band' photometry, the source shows variability which decay index is about -0.6 between 17:17(UT) and 18:33(UT). This source is therefore likely to be the optical afterglow of GRB 050408. Further analysis is in progress. This message may be cited." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3197 SUBJECT: GRB 050408: steepening of the optical decay DATE: 05/04/09 01:29:19 GMT FROM: Alberto Castro-Tirado at LAEFF-INTA M. Jelinek (IAA-CSIC Granada), T. Fathkullin, V. Komarova, T. Sokolova, V. Sokolov, V. Vlasyuk, Yu. Balega (SAO RAS, Russia), S. Guziy (Univ. of Nikolaev), A. de Ugarte Postigo, J. Gorosabel and A.J. Castro-Tirado (IAA-CSIC Granada), report: Further monitoring of the optical source reported by de Ugarte Postigo et al. (GCNC 3192), confirms a steepening of the optical decline, when comparing to the Huang et al. results (GCNC 3196). From the first frame obtained at the 6m SAO RAS telescope on Apr 8, 18:49 UT (this value supersedes the one given on GCN 3192) to the last one (at 21:38 UT), the object has declined significantly, implying a decay index alpha of -1.6 . An ID-chart is posted at: http://sirrah.cz/mates/grb050408.jpg . //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3198 SUBJECT: GRB 050408: First Optical observations with TFOSC at the RTT150 DATE: 05/04/09 02:08:11 GMT FROM: Irek Khamitov at TUG Z. Aslan,I. Khamitov,T. Ozisik, K. Uluc(TUG), U. Kiziloglu (METU),I. Bikmaev, R. Gumerov, N. Sakhibullin (KSU/AST), A. Alpar (SabUni), R. Burenin, M. Pavlinsky, R. Sunyaev (IKI), report: We have observed the error box of GRB 050408(GCN 3189 and GCN 3191) with TFOSC (the imaging and spectroscopic camera of the TUBITAK National Observatory, Turkey) attached to the Russian-Turkish 1.5-m telescope (Bakyrlytepe, Turkey). We made series of 30s and 60s exposures in Rc, starting at 18:46 UT. We have found the OT candidate indicated in GCN 3193 getting fainter with a spectral index of -0.63. We have determined its postion and magnitudes using USNO-B1. The position and the preliminary R photometry are as follows: RA: 12:02:17.31 Dec: +10:51:9.4 (+/- 0.1 arcsec)(2000) T-T0(hours) Rc 3.7 20.94 +/- 0.1 4.4 21.05 5.4 21.17 6.7 21.31 8.3 21.50 The reductions are in progress. This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3199 SUBJECT: GRB 050408: Magellan astrometry and photometry DATE: 05/04/09 02:27:11 GMT FROM: Josh Bloom at Harvard/CFA H.- W. Chen (MIT), Paul J. Green (CfA), J. S. Bloom (UCB), & J. X. Prochaska (UCSC) report on behalf of the GRAASP collaboration: "We began imaging the position of GRB050408 at 00:12, April 9 (UT), using IMACS on the Magellan/Baade telescope in the R and I bands. The afterglow candidate reported by de Ugarte Postigo et al. (GCN #3193) is detected in both bandpasses. Based on a comparison with objects found in the 2MASS catalog, we measured the coordinates of the afterglow as RA(J2000)= 12:02:17.328 and Dec(J2000)=+10:51:09.47 with an error of 250 mas in each coordinate. We also measure the afterglow brightness to be R = 21.7 +/- 0.1 mag and I = 21.4 +/- 0.1 mag with R-I=0.3, 7h50m after the initial trigger." This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3200 SUBJECT: GRB 050408: Mercator Optical Observations DATE: 05/04/09 05:17:53 GMT FROM: Peter Curran at U of Amsterdam K. Wiersema, P. Curran (University of Amsterdam), K. Lefever, H. van Winckel, C. Waelkens (Katholieke Universiteit Leuven), O. van Braam, Y. Grange, R. de Rooij, A. de Vries, L. Waters, (University of Amsterdam), report: "We have taken R- and I-band images of the optical afterglow reported by de Ugarte Postigo et al. (GCN 3193) of the HETE-2 GRB 050408 (Sakamoto et al., GCN 3189) at the 1.2m Mercator Telescope at La Palma. The R-band observation started at 20:56 UT and consisted of 3 x 5m, 1 x 3m and 1 x 8m exposure time, making the total exposure time 26 minutes, with midpoint 4.82h after burst. The I-band observation started at 21:30 UT and consisted of 2 x 5 minutes exposure time, with midpoint 5.22h after burst. We calibrate our photometry using the USNO-B catalogue values. We find an R-band magnitude of 21.25 +/- 0.2 and a I-band magnitude of 20.4 +/- 0.3. We thank the staff of the Mercator Telescope for the excellent assistance." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3201 SUBJECT: GRB 050408: Emission and absorption redshift DATE: 05/04/09 07:17:46 GMT FROM: Edo Berger at Carnegie Obs Edo Berger, Mike Gladders, and Gus Oemler (Carnegie Observatories) report: "On 2005, April 9.22 UT we obtained a spectrum of the optical afterglow (GCN 3193) of GRB 050408 (GCN 3189) with LDSS-3 on the Magellan/Clay telescope. We find a broad emission line which we interpret as [OII]3727 at a redshift of z=1.236 and an absorption doublet which we interpret as MgII 2796/2803 at the same redshift. Given a fluence of about 3.3e-6 erg/cm^2 the isotropic-equivalent gamma-ray energy is 1.3e52 erg." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3202 SUBJECT: GRB 050408 Optical Observations DATE: 05/04/09 07:47:47 GMT FROM: Kuntal Mishra at ARIES,Nainital,India Kuntal Misra, S. B. Pandey (ARIES Naini Tal) and Atish P. Kamble (Raman Research Institute, Bangalore) on behalf of larger Indian GRB collaboration We acquired V, R, I frames of GRB 050408 error box localized by HETE-II (GCN 3189) and SWIFT (GCN 3191) around 2 hours after the burst in thin cloudy conditions. The afterglow candidate by Postigo et al. (GCN 3192) is seen in our frames. The magnitude of our frame taken around 2.4 hours after the burst (exp-time 300secx2) is R_c = 20.4 +/- 0.2, calibrated with respect to USNO B1.0 stars 1008-0199794 (R ~ 16.62) and 1008-0199752 (R ~ 15.89). Our derived magnitude in combination with the R band magnitudes by Aslan et al. (GCN 3198) follow the power law decay index of 0.70 +/- 0.06, consistent to those by Huang et al. (GCN 3196) and Aslan et al. (GCN 3198). This message can be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3203 SUBJECT: GRB 050408,optical observation DATE: 05/04/09 08:04:43 GMT FROM: Shouta Maeno at U.of Miyazaki S.Maeno,E.Sonoda,Y.Tokunaga,M.Yamauchi (University of Miyazaki) "We have observed the field covering the error circle of GRB 050408 (GCN 3189;HETE Trigger time is 16:22:50.93 UT) with the unfiltered CCD camera on the 30-cm telescope at University of Miyazaki. The observation was started 16:52:23 UT on Apr.8. After co-adding a set of 20 images (16:52:23 UT - 17:29:14 UT) of 30 sec exposures, we have compared with the USNO-A2.0 catalog. Preliminary analysis shows there is no new source brighter than 17.6 mag. at the reported position by A. de Ugarte Postigo et al. (GCN3192). " //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3204 SUBJECT: GRB 050408: Moderate-resolution Gemini Spectroscopy DATE: 05/04/09 09:41:01 GMT FROM: Josh Bloom at Harvard/CFA Jason X. Prochaska (UCO/Lick Obs.), J. S. Bloom (UCB), H.-W. Chen (MIT), R. J. Foley (UCB) & K. Roth (Gemini Obs.) report on behalf of the GRAASP collaboration: "We acquired a Gemini/GMOS optical spectrum (R~3000) of the afterglow GRB 050408 (GCN #3189) on UT April 9.42. We identify MgI absorption at a heliocentric redshift of z=1.2357 +/- 0.0002, consistent with the previously reported value (GCN #3201). In addition we confirm the presence of a resolved emission doublet consistent with redshifted [OII]3727. We also report tentative detections of the TiII 3230, 3384 transitions suggesting the gas associated with the host galaxy is relatively dust poor and/or high in metal content." We thank the Gemini observing staff for assistance. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3205 SUBJECT: GRB050408: REM NIR and Optical observation DATE: 05/04/09 10:36:40 GMT FROM: Andrea Melandri at Rome Astro Obs A. Melandri, L. A. Antonelli, S. Covino, V. Testa, A. Monfardini, E. Palazzi, G. Chincarini, F. M. Zerbi, G. Tosti, E. Molinari, L. Nicastro, F. Vitali, on behalf of the REM/ROSS team, report: "On Apr 9, 2005 the REM telescope observed the field of GRB050408 (Sakamoto et al. GCN 3189) from La Silla Observatory (Chile). The field was imaged with both REM instruments REM-IR and ROSS in V, R, I, J, H and Ks filters starting at 00:31 UT (approximately 8.2 hours after the burst) for a total integration time of 200 seconds for each filter. No sources are detected within SWIFT XRT error circle (Wells et al. GCN 3191) and at the position of the Optical Transient (Ugarte et al., GCN 3192; Huang et al., GCN 3196) down to a limiting magnitude of 18.5, 18.3, 17.9, 16.8, 17.4, 18.4 (5-sigma upper limit) This message can be cited." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3206 SUBJECT: GRB 050408, optical observations DATE: 05/04/09 11:57:15 GMT FROM: Vasilij Rumjantsev at CrAO V.Rumyantsev (CrAO), V.Biryukov (SAI, MSU), and A.Pozanenko (IKI) on behalf of larger GRB follow up collaboration report: We have obtained 20 unfiltered images of the GRB050408 (HETE 3711) error box (Sakamoto et al., GCN 3189). The images were taken with the AT-64 telescope of Crimean Astrophysical observatory and cover the period UT 18:19:33 - 18:45:57 of April 08, 2005. No source was detected within SWIFT XRT error box (Wells et al. GCN 3191) and at the position of the optical transient (Ugarte et al., GCN 3192). Best limiting magnitude of the combined image (S/N=3) calibrated against R USNO-A2.0 is following Mid Time(UT) telescope exposure limiting mag. April 08 18:33 AT-64 20x60 s 19.9 This message can be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3207 SUBJECT: GRB 050408: Optical limit at 20 min after the burst DATE: 05/04/09 12:27:01 GMT FROM: Yuji Urata at RIKEN T. Mizuno, Y. Arai, H. Yamagishi (Tokyo Gakugei Univ.), T. Soyano (Kiso observatory), Y. Urata, T. Tamagawa(RIKEN), K.Y. Huang(NCU) on behalf of EAFON report, " We have imaged the entire error region of GRB 050408 (GCN3189) with 1.05m Schmidt telescope at Kiso observatory, Japan in R band. Utilizing HETE-2 GCN alert, the observation was started at 16:42 UT (20 min after the burst) and lasted to 1 hour. There is no optical emission from the optical afterglow (GCN 3192, GCN 3196) down to a limiting magnitude of R=19.1 as estimated using USNO B1.0 catalog. This message may be cited." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3208 SUBJECT: GRB 050408, SMARTS optical/IR afterglow observations DATE: 05/04/09 16:21:14 GMT FROM: Bethany Cobb at Yale U B. E. Cobb and C. D. Bailyn (Yale), part of the larger SMARTS consortium, report: Using the ANDICAM instrument on the 1.3m telescope at CTIO, we obtained optical/IR imaging of the error region of GRB 050408 (GCN 3189, Sakamoto et al.) beginning ~10.9 hours post-burst (2005-04-09 03:14 UT). Total summed exposure times amounted to 36 minutes in I and 30 minutes in J. The optical afterglow reported by de Ugarte Postigo et al. (GCN 3193) is detected in both our I and J-band images, though the source appears only slightly above the background in J. Preliminary comparison with Landolt standard stars yields an I magnitude of 21.3+/-0.1. Comparison with IR standard stars LCO-LHS2397a and PERSSON-P9144 yields a J magnitude of 21.0+/-0.8. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3209 SUBJECT: GRB 050408: Swift XRT analysis DATE: 05/04/09 17:07:34 GMT FROM: David Burrows at PSU/Swift G. Chincharini, P. Romano, S. Campana, C. Pagani, G. Tagliaferri (INAF-OAB), M. Capalbi, P. Giommi (ASDC), J. Kennea, D. N. Burrows (PSU), A. Wells, O. Godet (U. Leicester), G. Cusumano, V. Mangano (IASF/Palermo), L. Cominsky (Sonoma State U.), K. Hurley (UCB), and N. Gehrels (GSFC), report on behalf of the Swift XRT team: We have analyzed the Swift XRT data from GRB 050408 (Sakamoto et al. 2005, GCN 3189; Wells et al. 2005, GCN 3191) using 8 orbits with a total exposure time of 6417 s in Photon Counting (PC) mode. The refined coordinates of the X-ray afterglow are: RA(J2000) = 12:02:17.5 Dec(J2000) = +10:51:06.5 We estimate an uncertainty of 5 arcseconds radius (90% containment). This position is 3.9 arcsec from the optical candidates (De Ugarte-Postigo et al., GCN 3192; Chen et al., GCN 3199). The [0.2-10] keV light curve in PC mode starts 2555 seconds after the HETE-II trigger (T0). The count rate is decaying following a power law with a slope of about 0.8 over a time interval of 40 ks. With the current data we do not see evidence of a break in the XRT light curve. A preliminary spectral fit to the PC data gives a power law photon index of 2.2 +/- 0.2 in the [0.5-10] keV band, with a column density of (2.5+/-0.6)E21 cm^-2 (the Galactic value is 1.8E20 cm^-2). The average unabsorbed 0.5-10 keV flux is about 6.2E-12 erg cm^-2 s^-1 (in the time range 2.5-43.5 ks from trigger). //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3210 SUBJECT: GRB050408: Radio Observations DATE: 05/04/09 17:38:35 GMT FROM: Alicia Soderberg at Caltech A. M. Soderberg (Caltech) reports on behalf of the Caltech-NRAO-Carnegie GRB collaboration: "Using the Very Large Array at 8.5 GHz, we observed the field of GRB050408 (GCN 3189) on 2005 Apr 9.26 UT. We do not detect a radio source coincident with the X-ray or optical afterglow positions (GCNs 3191 and 3192). We place a 2-sigma limit of 74 uJy at the optical position. Further observations are planned." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3211 SUBJECT: GRB 050408: Mercator Optical Observations DATE: 05/04/09 23:43:33 GMT FROM: Klaas Wiersema at GRACE/U of Amsterdam P. Curran, K. Wiersema (University of Amsterdam), K. Lefever, H. van Winckel, C. Waelkens (Katholieke Universiteit Leuven), O. van Braam, Y. Grange, R. de Rooij, A. de Vries, L. Waters, (University of Amsterdam), G.Bourban, G.Burki, F.Carrier (Geneva Observatory), E. Rol (University of Leicester) report: "On 09 April we continued our observations (GCN 3200) of the optical afterglow reported by de Ugarte Postigo et al. (GCN 3193) of the HETE-2 GRB 050408 (Sakamoto et al., GCN 3189) at the 1.2m Mercator Telescope at La Palma. The R-band observation started at 05:15 UT and consisted of 2 x 8 minute exposures, with midpoint 13.02h after burst. We calibrated our photometry using the USNO-B catalogue. We find a marginal R-band detection of 22.3 +/- 0.3. We thank the staff of the Mercator Telescope for the excellent assistance." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3212 SUBJECT: GRB 050408: Properties of the Host Galaxy DATE: 05/04/10 00:57:26 GMT FROM: Don Lamb at U.Chicago GRB 050408: Properties of the Host Galaxy D. Q. Lamb, D. G. York, and D. E. Reichart report: The field of GRB 050408 (Sakamoto, et al., GCN Circular 3189) has been observed by the Sloan Digital Sky Survey and the data is publicly available as part of Data Release 3. Examination of the SDSS image of the field of GRB 050408 reveals a galaxy at RA = (180.57109 deg), Dec = (+10.85051 degree), coincident with the optical afterglow of GRB 050408. The magnitudes of the galaxy are u = 23.49, g = 23.30, r = 22.37, i = 21.95, and z = 21.39, with errors of +/- 0.01 mag, with the exception of the z band where the uncertainty is somewhat larger. These results suggest that light from the host galaxy may contribute significantly to the optical magnitudes reported for the optical afterglow of GRB 050408 as early as ~10 hours after the burst. This implies that continued Swift XRT observations of the X-ray afterglow of GRB 050408 (e.g., Wells et al., GCN Circular 3191; Chincharini et al. 3209) may be the only way of determining the light curve, and therefore the jet break time, for the afterglow of this burst. This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3213 SUBJECT: GRB 050408: SOAR UBVRc Observations DATE: 05/04/10 01:13:30 GMT FROM: Daniel E. Reichart at U.North Carolina M. Nysewander, S. Heathcote (CTIO), D. Reichart, M. Bayliss report on behalf of the UNC team of the FUN GRB Collaboration: We observed the afterglow of GRB 050408 (Sakamoto et al., GCN 3189; Wells et al., GCN 3191; de Ugarte Postigo et al., GCN 3192) with the 4.1-meter diameter SOAR Telescope at CTIO, using the SOAR Optical Imager. Beginning 9.3 hours after the burst, we observed for 10 x 200 sec in Rc, 9 x 200 sec in each of V and B, and 9 x 300 sec in U. The afterglow is well detected in Rc, V, and B. Between 9.3 and 10.7 hours after the burst, the Rc light curve faded with a temporal index of -2.23 +/- 0.60. However, between 10.7 and 13.4 hours after the burst, the temporal index is only -0.54 +/- 0.36. This suggests that the afterglow was fading rapidly but is now contaminated by a host galaxy. This confirms the host galaxy identified by Lamb et al. (GCN 3212) in the SDSS DR3. We are very grateful to the SOAR staff for supporting these observations during SOAR's commissioning period. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3214 SUBJECT: GRB 050408: WIDGET simultaneous optical observations DATE: 05/04/10 10:38:01 GMT FROM: Toru Tamagawa at RIKEN T. Tamagawa, Y. Urata (RIKEN), F. Usui (ISAS/JAXA), K. Onda, K. Abe, M. Tashiro (Saitama-U) on bealf of the WIDGET collaboration report: "The very widefield camera, WIDGET, located at Akeno, Japan, observed the region of HETE-2 error box for GRB 050408 (GCN 3189, Sakamoto et al.). We continuously monitored the HETE-2 field-of-view with repeat of unfiltered 5 sec exposures from 5 hours before the burst time to 4 hours after it. We have not found any optical emission at the afterglow position reported by Postigo et al. (GCN 3192) during our observation period. Coadding the ten images around the burst time yields the 1-sigma limiting magnitude of R~11 listed below, which was calibrated relative to USNO B1.0 catalogue. t-t0 (sec) start end limit mag. ------------------------------------- -293.93 -198.93 10.9 -193.93 -98.93 10.9 -93.93 1.07 10.9 6.07 101.07 11.0 106.07 201.07 10.9 ------------------------------------- Further analysis is in progress. This message may be cited. http://cosmic.riken.jp/grb/widget/" //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3215 SUBJECT: GRB 050408: Subaru Observations DATE: 05/04/10 11:26:35 GMT FROM: Nobuyuki Kawai at Tokyo Tech G. Kosugi, T. Yamada, H. Furusawa, Y. Matsuda, R. Yamauchi, Y. Nakamura, N. Kawai, and A. Yoshida report on behalf of the Subaru GRB team: "We have observed the position of GRB 050408 afterglow reported by de Ugarte Postigo et al. (GCN #3192) in z'-band with SuprimeCam on the Subaru 8.2m telescope atop Mauna Kea on Apr. 09 and 10, approximately 13.3 and 37.3 hours after the burst event, respectively. The seeing condition was around 0.6 arcsec for the both nights. We measured the afterglow brightness to be z'(Vega) = 21.2 +/- 0.2 and 22.0 +/- 0.2, and the temporal index to be -0.7. Although these magnitudes are inconsistent with the magnitude of the host galaxy candidate proposed by Lamb et al. (z = 21.39 mag; GCN #3212), the position of the proposed host coincides with a field galaxy (z'(AB)= 21.34 mag in our measurement) located 8 arcsec South-West to the afterglow." This message may be cited. [GCN_OPS(11apr05): Per author's request the "040508" in the Subject-line was changed to "050408".] //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3216 SUBJECT: GRB 050408: Inconsistency of host galaxy identification DATE: 05/04/10 12:45:35 GMT FROM: Alessandro Monfardini at JMU/Liverpool Robotic Tele A. Monfardini, I. Steele, C.G. Mundell C. Guidorzi, A. Gomboc, M. Bode (Liverpool), N. Tanvir (Hertfordshire), P. O'Brien and E. Rol (Leicester) report: "Since 4.3 hours after the burst, we are monitoring the field of the GRB050408 (HETE GCN 3189) with the 2m telescopes of the ROBONET network. We clearly detect the fading afterglow at the position suggested by A. de Ugarte Postigo et al. (GCN3192) and then refined in subsequent GCNs. We also detect the SDSS galaxy quoted by Lamb et al. (GCN3212) about 8arcsec from the afterglow position and conclude that this is VERY unlikely the GRB050408 host galaxy. This message can be cited." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3217 SUBJECT: GRB 050408: Retraction of Proposed Host Galaxy DATE: 05/04/10 13:38:51 GMT FROM: Don Lamb at U.Chicago GRB 050408: Retraction of Proposed Host Galaxy D. Q. Lamb, D. G. York, and D. E. Reichart report: We agree that the galaxy we proposed as the host galaxy of GRB 040508 lies ~ 8 arcsec South-West of the burst afterglow (Kosugi et al., GCN Circular 3215; Monfardini, GCN Circular 3216) and therefore cannot be the host galaxy of the burst. This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3222 SUBJECT: GRB 050408: Swift XRT measurement of possible jet break DATE: 05/04/10 20:00:03 GMT FROM: David Burrows at PSU/Swift O. Godet, K. L. Page, M. R. Goad, J. P. Osborne (U. Leicester), M. Capalbi, P. Giommi (ASDC), D. Grupe, D. N. Burrows (PSU), S. Campana, G. Chincarini (INAF-OAB), V. La Parola, T. Mineo (INAF-IASF/Palermo), S. Barthelmy, L. Angelini, N. Gehrels (GSFC), and P. Meszaros (PSU) report on behalf of the Swift XRT team: The Swift XRT instrument observed GRB 050408 as a Target of Opportunity for 20 ks (exposure time) on 8/9 April 2005, beginning 40 minutes after the HETE trigger and lasting for 60 ks of real time . Analysis of the data shows evidence for a possible jet break at about 24 ks post-burst, with the following parameters: initial slope: -0.71 +0.10/-0.12 Break time : 24 +25/-12 ks later slope -1.43 +0.72/-0.40 Both single power-law and broken power-law fits to the lightcurve are statistically acceptable at this point. Further observations planned for April 11 will give more information to help distinguish between the two and determine the jet break time. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3227 SUBJECT: GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT DATE: 05/04/10 22:54:37 GMT FROM: Stephen Holland at USRA/NASA/GSFC/SSC S. T. Holland (GSFC-USRA), M. Capalbi (ASDC), A. Morgan, S. Kobayashi, (PSU), A. Breeveld (MSSL), P. Boyd (GSFC-UMBC), N. Gehrels (GSFC), D. Hinshaw (GSFC-SPSYS), K. Mason (MSSL), J. Nousek (PSU), and A. Wells (Leicester) on behalf of the Swift UVOT team report: The Swift Ultra-Violet/Optical Telescope (UVOT) observed the field of GRB 050408 (Sakamoto et al., GCN 3189) starting at 17:07:08 UT on 8 April 2005. There is a faint source at the location of the optical afterglow (de Ugarte Postigo et al., GCN 3192) visible in the coadded U-band image. This source has U = 21.30 (-0.32,+0.45) mag and the total coadded exposure time is 2927 s. This source is at the 3-sigma detection limit of the coadded image and is only marginally consistent with being a point source. There is no detection in the other filters. The 3-sigma limiting magnitudes in a 3.5 arcsecond radius circular aperture , and the coadded exposure times, are: V = 21.3 (3866 s), B = 22.2 (2910 s), UVW1 = 17.8 (3223 s), UVM2 = 17.6 (1989 s), and UVW2 = 17.82 (3402 s). The magnitudes reported in this Circular are based upon preliminary flight calibrations. The first Swift/UVOT image of the field was a 100 s V-band exposure centred 45.117 minutes after the BAT trigger. No source is detected in this image down to a 3-sigma limiting magnitude of V = 19.9. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3228 SUBJECT: GRB 050408: PROMPT VRcIc Observations DATE: 05/04/10 23:35:56 GMT FROM: Matt Bayliss at UNC,Chapel Hill M. Bayliss, M. Nysewander, J. Haislip, J. A. Crain, A. Foster, J. Kirschbrown, C. MacLeod, and D. Reichart report on behalf of the UNC team of the FUN GRB Collaboration: We have observed the position of the GRB 050408 afterglow reported by de Ugarte Postigo et al. (GCN #3192) with three telescopes of the PROMPT robotic array, one in each of VRcIc. In one epoch of V-band observations, 122 x 60s exposures centered on April 9, 02:06:44 UT (t + 9.7 hours), we have a 3 sigma detection of the afterglow at V ~ 21.4. In a second epoch of 137 x 60s eposures centered at 05:37:31 UT (t + 13.2 hours) we do not detect the afterglow down to a limiting magnitude of V = 21.7 (2 sigma). V filter calibrations were made relative to 6 Nomad stars. PROMPT is still being built and commissioned. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3232 SUBJECT: GRB 050408: Optical limit DATE: 05/04/11 06:39:05 GMT FROM: Ken ichi Torii at RIKEN K. Torii (Osaka U.) reports "The error region of GRB 050408 (Sakamoto, et al. GCN 3189) was observed by the ART 14-inch telescope. BVRcIc imaging started at 2005 April 8, 16:23:48 UT (57-s after trigger) and 60-s exposure in each filter was repeated. The optical afterglow (de Ugarte Postigo, et al. GCN 3192) is not detected in our frames and the following 3-sigma upper limits are derived relative to USNO-A2.0 (R). MeanEpoch(UT) Magnitude Exposure 16:24:18 >16.2Rc 60s 16:28:50 >16.2Rc 60s 16:33:22 >17.0Rc 60sx5 " //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3234 SUBJECT: GRB050408: Radio Observations DATE: 05/04/11 17:10:52 GMT FROM: Alicia Soderberg at Caltech A. M. Soderberg (Caltech) reports on behalf of the Caltech-NRAO-Carnegie GRB collaboration: "Using the Very Large Array at 8.5 GHz, we observed again the field of GRB050408 (GCN 3189) on 2005 Apr 11.21 UT. We still do not detect a radio source coincident with the X-ray or optical afterglow positions (GCNs 3191 and 3192). Coaddition with our previous observation (GCN 3210) yields a flux of 74 +- 29 uJy at the optical position." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3246 SUBJECT: GRB 050408: SDSS Field Calibration DATE: 05/04/12 13:37:03 GMT FROM: Melissa Nysewander at UNC,Chapel Hill M. Nysewander, D. Reichart, D. Lamb, and D. York report: Using ugriz magnitudes from the SDSS DR3 and the transformation equations of Smith (2002; AJ, 123, 2121), we have calculated the UBVRcIc magnitudes of 50 sources in the field of GRB 050408: http://www.physics.unc.edu/~mnysewan/grb050408_fc.txt Systematic errors are typically 0.02 mag in the gri bands and 0.05 mag in the u and z bands. Statistical errors begin to dominate in u and z at roughly 21 mag and in gri at roughly 21.5-22 mag. All of these sources have been classified as stars by the SDSS frames pipeline; however, some of the fainter sources may be galaxies, regardless of this. Users can find the statistical and systematic error on the magnitude of any SDSS object in the field at http://cas.sdss.org/astro/en/tools/explore/obj.asp?ra=180.571087&dec=10.850506 by clicking on the "Field" button under "PhotoObj" in the column at the far left, and make their own decision about whether an object is a galaxy or a star at http://cas.sdss.org/astro/en/tools/chart/navi.asp?ra=180.571087&dec=10.850506 //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3254 SUBJECT: GRB 050408: refined XRT analysis, no jet break seen yet DATE: 05/04/12 19:26:43 GMT FROM: David Burrows at PSU/Swift M. Capalbi (ASDC), P. Romano (INAF-OAB), V. Mangano (INAF-IASF/Palermo), O. Godet (U. Leicester), L. Angelini (GSFC) and D. N. Burrows (PSU) report on behalf of the Swift XRT team: On 10 April 2004 we reported detection of a possible jet break in Swift XRT data on GRB 050408, with additional observations scheduled to verify the break in the light curve (Godet et al. 2005, GCN 3222). We now have analyzed new data extending to about 300,000 s after the burst, and can state that the reported possible jet break is not confirmed by the later observations. No jet break is seen in the XRT data up to 300,000 s after the burst. Additional observations are planned over the next several days to continue to search for a jet break in this afterglow. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3258 SUBJECT: GRB 050408: Kuiper 1.5m observations DATE: 05/04/13 19:37:03 GMT FROM: Peter A. Milne at super-LOTIS P.A.Milne, G.G.Williams (Steward Obs), H.-S.Park (LLNL), on behalf of the Super-LOTIS GRB team report: We have observed the field of GRB 050408 over two nights with the 1.5m Kuiper telescope on Mt. Bigelow, AZ., USA. We have performed BVRI broad-band imaging and have detected a source at a position consistent with that reported by A. de Ugarte Postigo et al. (GCN 3193). UT Mag Exp(sec) 9.16 R=21.888 +/- 0.150 11x120 9.18 I=21.305 +/- 0.203 9x120 9.20 V=22.069 +/- 0.171 11x120 9.26 R=21.963 +/- 0.129 8x300 9.29 I=20.691 +/- 0.132 8x300 9.32 V=22.618 +/- 0.191 7x300 9.35 B=22.369 +/- 0.166 6x300 10.26 I=22.288 +/- 0.390 4x300 10.29 V=23.480 +/- 0.612 4x300 The field was calibrated from Landolt fields observed during the first night. Two field stars were compared against the field calibration compiled by Nysewander et al. (GCN 3246). We were brighter in all cases, by 0.20/0.02/0.16/0.14 magnitudes for B/V/R/I respectively. Further observations are planned to obtain images suitable for use in image subtraction. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3261 SUBJECT: GRB050408: optical observation DATE: 05/04/13 20:25:10 GMT FROM: Alexei Pozanenko at IKI, Moscow B. Kahharov, M. Ibrahimov, D. Sharapov (MAO), A.Pozanenko (IKI), V.Rumyantsev (CrAO), G.Beskin (SAO) report: We observed the afterglow (Ugarte et al., GCN 3192) of the HETE GRB050408 (Sakamoto et al., GCN 3189) with 1.5m telescope of the Maidanak Astronomical Observatory (MAO), Uzbekistan under modarate weather conditions (seeing ~1.8 arcsec) on April 9 between 19:29:30 - 20:09:00 (UT). The optical source is clearly visible in the position of OT (Ugarte et al., GCN 3192; Huang et al., GCN 3196). A preliminary R-photometry against of USNO-B1.0 Catalog is the following: Mean time Exposure Mag. (UT) (s) Apr. 9.828 7x300 22.55 +/- 0.35 This message can be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3262 SUBJECT: GRB 050408: RTT150 optical observations DATE: 05/04/14 07:29:26 GMT FROM: Irek Khamitov at TUG I. Bikmaev, N. Sakhibullin (KSU/AST), Z. Aslan, I. Khamitov (TUG), U. Kiziloglu (METU), A. Alpar (SabUni), R. Burenin, M. Pavlinsky, R. Sunyaev (IKI), report: We have observed OT of GRB 050408 (A. de Ugarte Postigo et al., GCN 3192) with Rc-filter and ANDOR CCD at the Russian-Turkish 1.5-m telescope (RTT150, Bakyrlytepe, Turkey). We have made a set of 30 exposures with 5 min duration each during UT 18:30 - 20:10 , April 13. The weather was clear with average seeing of 1.8 arcsec. We have marginaly detected the OT at the limit of co-added frame with Rc = 23.7 +/-0.2 mag. We have re-reduced our previous observations (Aslan et al, GCN 3198) by using Landolt standard stars. RTT150 photometry of OT is given below: t-t0 (hours) Rc err exposure midtime (sec) 3.72 21.01 0.07 900 (30*30s) 4.37 21.10 0.05 1080 (18*60s) 4.89 21.25 0.05 960 (16*60s) 5.39 21.27 0.05 960 (16*60s) 5.79 21.44 0.06 960 (16*60s) 6.55 21.37 0.06 720 (12*60s) 6.85 21.50 0.06 720 (12*60s) 8.24 21.64 0.07 1200 (20*60s) 8.75 21.60 0.07 1200 (20*60s) 123.78 23.7 0.2 9000 (30*300s) The power law decay index between 3.7h and 8.7h calculated on the basis of the RTT150 data in Rc-band is -0.68+/-0.06 and the newly obtained value of Rc = 23.7 shows that the lightcurve is still fit by a single power law of -0.7 (GCN 3215, GCN 3222, GCN 3254). RTT150 optical light curve of OT GRB050408 is shown at http://www.tug.tubitak.gov.tr/~irekk/grb/grb050408/lc.jpg This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3508 SUBJECT: GRB 050408: jet break in the XRT light curve DATE: 05/06/01 18:38:09 GMT FROM: David Burrows at PSU/Swift S. Covino (OAB), M. Capalbi, M. Perri (ASDC), V. Mangano (INAF-IASF/Palermo), and D. N. Burrows (PSU) report on behalf of the Swift XRT team: We have analyzed the Swift XRT data from 12 observations of GRB 050408 (Sakamoto et al., GCN 3189) performed over a period of 38 days. The [0.3-10] keV light curve shows a break at (1.2 ± 0.5 )E5 seconds after the trigger. We interpret this as a jet break, implying a jet opening angle of 8.2 degrees, given an isotropic-equivalent gamma-ray energy of 1.3E52 erg (Berger et al., GCN 3201). //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3561 SUBJECT: GRB 050408: ARC 3.5-meter NIR Observations DATE: 05/07/02 15:17:43 GMT FROM: Don Lamb at U.Chicago GRB 050408: ARC 3.5-meter NIR Observations J. Flasher (Colorado), F. Hearty (Colorado), G. Stringfellow (Colorado), J. Walawender (Colorado), D. Q. Lamb (Chicago), T. Lisker (Washington), V. Debattista (Washington), J. Dembicky (APO), J. Barentine (APO), R. McMillan (APO), B. Ketzeback (APO), and D. G. York (Chicago) report on behalf of the ARC GRB team of the FUN GRB collaboration: We observed the afterglow (Wells et al., GCN Circular No. 3191; Postigo et al., GCN Circular No. 3192) of GRB 050408, a burst localized by HETE-2 (Sakamoto et al., GCN Circular No. 3189), on the night of April 8th, using NIC-FPS on the ARC 3.5-meter telescope at Apache Point Observatory. The observation began at 04.47 UT (12.29 hours after the burst) and ended at 07.06 UT (14.68 hours after the burst). The observation consisted of a series of 120-, 120-, 20-, and 20-second exposures in Z, J, H, and Ks, respectively. We have constructed stacked images of the GRB field, corresponding to 20-minute exposures in each filter. We detect the afterglow in all four filters, and measure Z = 21.8 ± 0.12, calibrated relative to the SDSS stars in the field. NIC-FPS is currently in its commissioning phase. This message may be cited.