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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').
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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"

32509 results found.

  1. GRB040323: NIR Observations and Variable Object
  2. GRB 040319 (=H3128): An X-Ray-Rich GRB Localized by the HETE-2 WXM and SXC
  3. GRB 040323, a dark GRB ?
  4. GRB040223: Deep NIR NTT data re-analysis
  5. GRB 040223: XMM-Newton results
  6. GRB040223, improved XMM position
  7. GRB 031203: spectoscopic evidence for a 1998bw-like SN
  8. GRB 031203, possible supernova
  9. IBAS results on a burst from SGR1806-20
  10. GRB 040228 Optical observations
  11. IPN triangulation of GRB040228 (H3066, H3067)
  12. GRB 040228 (=H3066?,=H3067?): A Long GRB Localized by the HETE-2 WXM
  13. GRB 040223: Deep NIR NTT observations
  14. GRB 040223 : Optical observation (non-detection)
  15. XMM-Newton Images of GRB 040223
  16. GRB 040223, VLA observations
  17. GRB 040223: REM IJK Observations
  18. GRB 040223 XMM-Newton observation ...
  19. GRB 031203 XMM-Newton observation
  20. GRB031111, optical observations
  21. GRB031220: 2nd Chandra observation and X-ray afterglow candidate
  22. GRB031203: Chandra Observations
  23. GRB040106, follow-up radio observations
  24. GRB040106: refined X-ray transient position
  25. Follow-up on IBAS GRB Alert 1379
  26. SN 2003dh/GRB030329 late-time optical spectroscopy
  27. GRB040106, Radio Observations
  28. GRB040106, likely optical afterglow
  29. GRB040106: Second Epoch Optical Observations
  30. GRB 031220: Optical observations of Chandra X-ray sources
  31. XMM-Newton Images of GRB 040106
  32. GRB040106: optical observations with REM+ROSS
  33. GRB031220: observation at Univercity of Miyazaki
  34. GRB 040106: Optical observations
  35. XMM-Newton observation of GRB040106
  36. GRB031220(=H2976): TNG R-band Observation of the Chandra X-ray Sources
  37. GRB031220(=H2976): Observation with the Chandra X-ray Observatory
  38. GRB 031203 I-band monitoring
  39. IPN triangulation of GRB031214 (short/hard; very intense; small error box)
  40. GRB 2974 follow-up observations
  41. GRB031203, improved XMM position
  42. GRB 031203: SMARTS optical monitoring
  43. GRB 021203: A Normal GRB viewed far off axis?
  44. GRB 031203: Variable Radio Source
  45. GRB 031203: Magellan spectrum of possible GRB host
  46. GRB 031203: Optical/IR Astrometry
  47. GRB031203 K prime photometry: correction to galaxy coordinates
  48. GRB031203: ROSAT upper limits suggest XMM-S1 source as the transient
  49. XMM-Newton Observation of GRB031203
  50. GRB031203: K' Photometry of the likely GRB host
  51. XMM-Newton Observation of GRB031203
  52. GRB 031203: Radio detection
  53. GRB 031203: Further reports on December 4 observations
  54. GRB 031203: IR NTTobservations do not confirm REM detection
  55. GRB 031203: z ~ 10 or Fragmented Dust in the Circumburst Environment?
  56. GRB 031203: Apparent Spectral Break
  57. GRB031203: Planned XMM-Newton observation II
  58. GRB 031203: IR REM Observations
  59. GRB031203: Optical Observations
  60. GRB 031203 XMM-Newton observation
  61. GRB 031203: Optical/IR SMARTS Observations
  62. GRB031203: Planned XMM-Newton observation
  63. GRB031111A, prompt optical observations
  64. GRB 031111, Radio observations
  65. GRB 031111: Optical observations
  66. GRB 031111, optical observations
  67. SN 2003jd (SN/GRB?) -- X-ray Observations
  68. IPN triangulation of GRB031111 (=H2924): small error box
  69. XRF031109 (=H2919): A very long XRF localized by HETE
  70. GRB031026: 1.2mm upper limit with MAMBO at the IRAM 30m
  71. GRB030929/SN2003jd association unlikely based on IPN localiztion
  72. Lulin optical follow-up observations of GRB031026
  73. SN 2003jd (SN/GRB?), Radio Observations
  74. SN 2003jd (SN/GRB?) - possible association with GRB 030929
  75. GRB 031026: Further Ic Observations
  76. GRB 031026 (=H2882): Evidence for High Redshift from Prompt
  77. Peculiar Type Ic SN 2003jd (SN/GRB?), optical spectrum
  78. IPN triangulation of GRB031024 (single error box)
  79. GRB031026 (=H2882): A Long, Hard Spectrum Burst Localized by HETE
  80. XRF 030824: additional observations at CFHT
  81. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  82. SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
  83. XRF 030723: Subaru Optical Observations
  84. XRF 030824: Early follow-up observation at Kiso observatory
  85. XRF 030723: Detection of the likely host galaxy
  86. XRF030824 (=H2821): An X-Ray Flash Localized by the HETE WXM
  87. XRF030823 (=H2818): An X-Ray Flash Localized by the HETE WXM and SXC
  88. IPN triangulation of GRB030922A (large error box)
  89. IPN triangulation of GRB030921 (large error box)
  90. GRB030913: Subaru Optical Observations
  91. GRB 030913: ROTSE-3c Optical Observations
  92. GRB030913: OT's limit by MASTER
  93. GRB030913, candidate afterglow observations
  94. GRB030913: AAVSO optical observations
  95. GRB030913 (=H2849): Confirmation of the Flight Localization
  96. GRB030913 (=H2849): TAROT Observations
  97. Magellan Observations of GRB030725 (=H2779)
  98. GRB030913 (=H2849): A GRB Possibly Localized by HETE
  99. IBAS detection of bursts from SGR 1806-20
  100. Radio Observations of SGR1806-20

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