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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"

35981 results found.

  1. IBAS Alerts 1771 and 1772: NOT a real GRB
  2. GRB and XRF on April 27, 2004. Detection by Konus-Wind and Helicon (Coronas-F)
  3. IPN triangulation of GRB040425 (=H3183)
  4. GRB040422: optical observations at CrAO
  5. GRB 040423 (=H3175): A Long GRB Localized by HETE
  6. GRB 040422: ROTSE-IIIb Prompt Optical Limits
  7. GRB040422, BVRcIc field calibration
  8. GRB 040422,optical observation
  9. GRB 040422: a long GRB detected with INTEGRAL
  10. GRB 040403, deep optical observations
  11. INTEGRAL-SPI/ACS GRB data: timing correction
  12. IBAS GRB alerts 1739, 1740, 1741
  13. HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
  14. GRB 040403: Optical Observations
  15. GRB 040403 Optical Observations
  16. GRB 040403: Optical observations
  17. GRB 040403: optical observations
  18. GRB 040403: Optical Observations
  19. GRB 040403: a long GRB detected with INTEGRAL
  20. GRB 040329: hard burst detected by Konus-Wind and Helicon - Coronas-F
  21. IBAS GRB Alert 1694
  22. GRB 040319 (=H3128): An X-Ray-Rich GRB Localized by the HETE-2 WXM and SXC
  23. GRB 040323, a dark GRB ?
  24. short hard GRB 040322
  25. GRB 040323: a long GRB detected with INTEGRAL
  26. IBAS GRB alerts 1679, 1680, 1681
  27. GRB040223: Deep NIR NTT data re-analysis
  28. GRB 040223: XMM-Newton results
  29. GRB040223, improved XMM position
  30. IBAS Alert 1678: not a GRB
  31. GRB 031203: spectoscopic evidence for a 1998bw-like SN
  32. GRB 031203, possible supernova
  33. GRB 040228 Optical observations
  34. IPN triangulation of GRB040228 (H3066, H3067)
  35. GRB040228 : KISO optical follow-up observation
  36. GRB 040228 (=H3066?,=H3067?): A Long GRB Localized by the HETE-2 WXM
  37. GRB 040223: Deep NIR NTT observations
  38. GRB 040223 : Optical observation (non-detection)
  39. XMM-Newton Images of GRB 040223
  40. GRB 040223, VLA observations
  41. GRB 040223: REM IJK Observations
  42. GRB 040223 XMM-Newton observation ...
  43. GRB 031203 XMM-Newton observation
  44. GRB 040223 : Planned XMM-Newton observation
  45. GRB 040106 : Planned XMM-Newton observation
  46. GRB 040223: further offline analysis
  47. GRB 040223: a long GRB detected with INTEGRAL
  48. Follow-up on IBAS GRB Alert 1379
  49. IBAS GRB alert 1379
  50. SN 2003dh/GRB030329 late-time optical spectroscopy
  51. GRB040106, likely optical afterglow
  52. GRB040106: Second Epoch Optical Observations
  53. GRB 031220: Optical observations of Chandra X-ray sources
  54. XMM-Newton Images of GRB 040106
  55. GRB040106: optical observations with REM+ROSS
  56. GRB031220: observation at Univercity of Miyazaki
  57. GRB 040106: Optical observations
  58. GRB 040106 : Planned XMM-Newton observation
  59. GRB 040106 : peak flux
  60. GRB 040106 : a long GRB detected with INTEGRAL
  61. IPN triangulation of an intermediate burst from SGR1806-20
  62. GRB031220(=H2976): TNG R-band Observation of the Chandra X-ray Sources
  63. GRB031225a triangulation (annulus)
  64. IPN triangulation of GRB031219 (large error box)
  65. GRB031220: Palomar Observations
  66. GRB 031220 : Kyoto Optical Observation
  67. GRB 031220: Subaru observation
  68. GRB 031220: Optical observation at Tokyo Tech
  69. GRB031220 : Optical Observation of Lulin Observatory
  70. GRB 031203 I-band monitoring
  71. IPN triangulation of GRB031214 (short/hard; very intense; small error box)
  72. GRB 2974 follow-up observations
  73. GRB 031203: Discovery of a dust echo
  74. GRB031214 triangulation (annulus), [repost of GCN2487, subject corrected]
  75. GRB030921 triangulation (annulus)
  76. GRB 031203: SMARTS optical monitoring
  77. GRB 021203: A Normal GRB viewed far off axis?
  78. GRB 031203: Variable Radio Source
  79. GRB 031203: Magellan spectrum of possible GRB host
  80. GRB 031203: Optical/IR Astrometry
  81. IPN/HETE localization of GRB031203B (=H2949; large error box)
  82. GRB031203: ROSAT upper limits suggest XMM-S1 source as the transient
  83. GRB 031203: Deep NIR NTT & VLT observations
  84. GRB031203: K' Photometry of the likely GRB host
  85. GRB 031203: Radio detection
  86. GRB 031203: Further reports on December 4 observations
  87. GRB 031203: IR NTTobservations do not confirm REM detection
  88. GRB031203 : Optical Observation of Lulin Observatory
  89. GRB 031203: z ~ 10 or Fragmented Dust in the Circumburst Environment?
  90. GRB 031203: Apparent Spectral Break
  91. GRB 031203: IR REM Observations
  92. GRB031203: Optical Observations
  93. GRB 031203 XMM-Newton observation
  94. GRB 031203: Optical/IR SMARTS Observations
  95. IPN triangulation of GRB031127A and B (quasi-simultaneous; large error boxes)
  96. GRB 031203: further analysis of INTEGRAL data
  97. GRB 031203: A long GRB detected with INTEGRAL
  98. IPN triangulation of GRB031201 (large error box)
  99. IPN triangulation of GRB031130 (large error box)
  100. GRB031111A, prompt optical observations

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