TITLE: GCN GRB OBSERVATION REPORT NUMBER: 5027 SUBJECT: GRB 060428B: KAIT observations DATE: 06/04/28 17:18:35 GMT FROM: Weidong Li at UC Berkeley KAIT/LOSS From alex@wormhole.Berkeley.EDU Fri Apr 28 10:07:14 2006 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.1.0 (2005-09-13) on chandra X-Spam-Level: X-Spam-Status: No, score=-103.8 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_00, USER_IN_WHITELIST autolearn=ham version=3.1.0 X-Original-To: wli@astro.berkeley.edu Delivered-To: weidong@astro.berkeley.edu Received: from wormhole.Berkeley.EDU (wormhole [128.32.92.127]) by chandra.berkeley.edu (Postfix) with ESMTP id 77CD2793AF for ; Fri, 28 Apr 2006 10:07:14 -0700 (PDT) Received: (from alex@localhost) by wormhole.Berkeley.EDU (8.11.7/8.11.4) id k3SH7D222376 for wli@astro.berkeley.edu; Fri, 28 Apr 2006 10:07:13 -0700 (PDT) Date: Fri, 28 Apr 2006 10:07:13 -0700 (PDT) From: Alex Filippenko Message-Id: <200604281707.k3SH7D222376@wormhole.Berkeley.EDU> To: Weidong Li Subject: here it is, slightly edited Status: R Content-Length: 2096 W. Li, R. Chornock, N. Butler, J. Bloom, and A. V. Filippenko (University of California, Berkeley), on behalf of the KAIT GRB team, report: The robotic 0.76-m Katzman Automatic Imaging Telescope (KAIT) at Lick Observatory observed GRB 060428B, detected with Swift (Trigger 207399; Campana et al. GCN 5017). The automatic sequence started at 08:57:50, 192 s after the burst. In a 15 s unfiltered image, no afterglow candidate is detected to a limiting magnitude of 18.7 (from comparison with the USNO B1.0 catalog). Our real-time image processing software detected the optical afterglow candidate reported by Price et al. (GCN 5019) in a 60 s unfiltered image started at 642 s after the burst, with the following precise (+/- 0.3") position: RA = 15:41:25.63 Dec = +62:01:30.3 (J2000.) A table of photometry (3-sigma limits and detections) is reported below. The photometry of the afterglow candidate suggests a flat luminosity evolution from 10 to 35 minutes after the burst, but we caution that the photometry may suffer larger uncertainties than reported due to relatively poor detections and the contamination of a nearby source. ====================================================================== Start UT t(GRB) exposure(s) Filter 3sigma-limit detection 08:57:50 192s 15.0 clear 18.7 08:58:27 229s 15.0 V 16.9 08:58:57 259s 15.0 I 17.2 08:59:28 290s 20.0 clear 19.0 09:00:04 326s 45.0 V 17.7 09:01:04 386s 45.0 I 18.3 09:02:05 427s 45.0 clear 19.2 09:03:07 489s 60.0 V 17.9 09:04:23 565s 60.0 I 18.3 09:05:40 642s 60.0 clear 19.58 +/- 0.13 09:10:51 953s 120.0 clear 19.64 +/- 0.13 09:18:51 1433s 240.0 clear 19.40 +/- 0.11 09:30:55 2157s 360.0 clear 19.52 +/- 0.11 ========================================================================