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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

2744 results found.

  1. GRB041219; RXTE ASM Observations
  2. GRB 041218: optical observations
  3. Deep RAPTOR observations during GRB 041219
  4. GRB041219c: Third Burst in One Day from Swift-BAT
  5. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  6. GRB 041217: LCO40 Optical Observations and Possible Candidates
  7. GRB 041211: Infrared Observations
  8. GRB 041006 R observations in Loiano
  9. GRB041006, optical observation in CrAO
  10. Search for SN light in XRF 040912 with MEGACAM
  11. GRB 040916: Afterglow Color at Early Times
  12. GRB041006 (=HETE3570): optical observations
  13. GRB 040924: detection of possible host galaxy by Subaru
  14. GRB 040924: RTT150 optical observations
  15. XRF040916: continuing decay of OT
  16. XRF 040912, identification of CXO sources
  17. GRB040912 (= H3557): Chandra Observations Scheduled
  18. GRB040903 - A XRF?
  19. GRB040827: analysis of the XMM-Newton observation
  20. ROTSE-III Rapid Response to possible GRB 040903 (INTEGRAL #1972)
  21. Possible GRB 040903 - further analysis
  22. Possible GRB 040903 detected with INTEGRAL
  23. GRB 040827: Possible detection of optical afterglow
  24. MASTER: GRB040827 possible OT
  25. GRB040825A: optical observations
  26. GRB040825B: optical observations
  27. GRB040825B: Correction to GCN 2657
  28. XRF040812: possible afterglow second Chandra observation
  29. XRF040812: possible afterglow
  30. GRB040624: optical monitoring at TNG
  31. XRF 040701 - optical observations of the decaying Chandra source
  32. GRB040706:observation at University of Miyazaki
  33. GRB 040511: NIR observations with REM
  34. GRB 040423 (=H3175): A Long GRB Localized by HETE
  35. GRB 031203, possible supernova
  36. IPN triangulation of GRB040228 (H3066, H3067)
  37. GRB 031220: Optical observations of Chandra X-ray sources
  38. GRB040106: optical observations with REM+ROSS
  39. IPN triangulation of GRB031219 (large error box)
  40. GRB 031203: Magellan spectrum of possible GRB host
  41. GRB 031203: IR NTTobservations do not confirm REM detection
  42. GRB 031203: IR REM Observations
  43. IPN triangulation of GRB031107 (two large error boxes)
  44. GRB031026: 1.2mm upper limit with MAMBO at the IRAM 30m
  45. SN 2003jd (SN/GRB?) - possible association with GRB 030929
  46. GRB 031026 (=H2882): Evidence for High Redshift from Prompt
  47. XRF 030824: additional observations at CFHT
  48. IPN detection of continued activity from SGR1806-20
  49. XRF 030824: observations at CFHT
  50. XRF030823 (=H2818): An X-Ray Flash Localized by the HETE WXM and SXC
  51. GRB030922 triangulation (annulus)
  52. GRB030913: OT's limit by MASTER
  53. GRB 030913, optical candidate
  54. IPN triangulation of GRB030916 (possible short/hard GRB; large error box)
  55. GRB030913 (=H2849): TAROT Observations
  56. GRB030913 (=H2849): A GRB Possibly Localized by HETE
  57. IPN triangulation of GRB030908 (annulus)
  58. IPN detection of continued activity from SGR1806-20
  59. SGR 1808-20 (=H2802): A Possible new SGR
  60. XRF030723: Re-analysis of ROTSE-III early images
  61. GRB030725, possible optical transient
  62. RXTE PCA Observations of SGR1806-20 Region
  63. IPN triangulation of GRB030711 (annulus, =SGR0525-66?)
  64. MASTER: optical observation GRB030601
  65. GRB 030329: Correction to GCN 2254
  66. GRB 030329: Optical Observations
  67. GRB 030329/SN 2003dh: Possible increase in brightness
  68. GRB 021004: HST observations
  69. IPN triangulation of GRB030518B (annulus)
  70. GRB030429: RTT150 optical observations, a possible host galaxy
  71. GRB 030501: TAROT possible candidate counterpart
  72. GRB030429, possible optical counterpart
  73. SNeIa AS THE POSSIBLE PROGENITORS OF SHORT-DURATION GRBs.
  74. Optical Observations of GRB 030418 with Magellan
  75. IPN triangulation of GRB030422C (annulus)
  76. GRB 030329: SARA Optical Observations
  77. OT GRB 030329: early spectrum
  78. IPN triangulation of GRB030410 (annulus)
  79. GRB 030329, color evolution
  80. GRB030329: Optical observcations
  81. GRB 030329: possible color change
  82. OT GRB light curves and SN predictions
  83. GRB 030329: fitting parameters and re-brightening
  84. GRB 030329: optical observations
  85. 030331 NOT A GRB
  86. GRB030329: ROTSE network observes steepening of decay curve
  87. GRB 030329: optical observations
  88. GRB 030329 follow-up
  89. Possible GRB030323 localized by INTEGRAL
  90. IPN triangulation of GRB030325 (final analysis)
  91. IPN triangulation of GRB030325 (two small error boxes)
  92. GRB030323, ROTSE-III detection of possible optical counterpart
  93. GRB030324, BVRcIc field photometry
  94. GRB030323, possible optical counterpart
  95. GRB030323, BVRcIc field calibration
  96. Possible GRB 030320 localized by INTEGRAL
  97. IPN triangulation of GRB030306 (two small error boxes)
  98. GRB 030226: Ic Observations
  99. GRB 030227 optical afterglow
  100. 030302: NOT A GRB

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