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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.

Advanced Search Examples (click to copy):

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

19548 results found.

  1. GRB 060605 new redshift
  2. GRB 070125, deep late-time optical observation
  3. VLA observation of GRB 070224
  4. GRB 070227: Swift/UVOT Upper Limits
  5. GRB 070227: TAROT La Silla observatory optical observations
  6. GRB 070227, Swift-BAT refined analysis
  7. GRB070227: possible X-ray afterglow detection
  8. GRB 070227: Swift detection of a burst in ground analysis
  9. GRB 070224: Swift/UVOT Upper Limits
  10. VLA observation of GRB 070223
  11. VLA observation of GRB 070220
  12. GRB070224: Magellan Imaging Observations
  13. GRB 070224: WHT K-band imaging
  14. GRB 070224: MDM Observations
  15. GRB070224: Gemini Imaging Observations
  16. GRB 070224: SARA upper limit
  17. GRB 070224: optical afterglow candidate
  18. GRB 070224: MASTER-Net refind analysis
  19. GRB 070224: MASTER-VWF-Kislovodsk observations
  20. GRB 070224: Swift detection of a burst
  21. GRB 070223: Optical observations
  22. GRB070223: Swift/UVOT refined analysis
  23. GRB 070223: Optical-IR observation with KANATA
  24. GRB070223: MASTER-VWF-Kislovodsk observations
  25. GRB070223 - SDSS Pre-Burst Observations
  26. GRB070223: Swift burst
  27. GRB 070220: MITSuME Okayama Optical Observation
  28. Swift/UVOT refined analysis of GRB070220
  29. GRB 070209: Swift XRT refined analysis
  30. GRB 070220: Observation with the KANATA 1.5m telescope
  31. GRB 070219: Gemini Observations
  32. GRB 070220: Swift detection of a burst
  33. GRB070219: MASTER-VWF-Kislovodsk observations
  34. GRB 070219: Swift/UVOT Upper limits
  35. GRB 070219: I-band observations
  36. GRB 070219: optical TNG observations
  37. GRB070219 - SDSS Pre-Burst Observations
  38. GRB 070125 observations with the GMRT
  39. GRB 070129: MDM I-band Detection
  40. GRB 070201: IPN constraints and nearby galaxies
  41. GRB 070208: MARGE Optical Observations
  42. GRB 070209, Swift-BAT refined analysis of the short hard burst
  43. GRB 070209: Swift detection of a short hard burst
  44. GRB070208: Absorption and emission redshift from Gemini
  45. GRB 070208: MDM Optical Decay
  46. GRB070208 - SDSS Pre-Burst Observations
  47. GRB 070208: MDM Observations
  48. GRB 070208: Swift detection of a burst
  49. GRB 070125 detection with CARMA
  50. GRB 070129: afterglow confirmation
  51. GRB070126: Swift-XRT Observation
  52. GRB 070129: Swift/UVOT Upper limits
  53. GRB 070129: Xinglong TNT optical Upper Limit
  54. GRB 070129: Swift-XRT Refined Analysis
  55. GRB 070129: VLT observations
  56. GRB 070125: An IR Point Source and an Apparent Host Galaxy
  57. GRB 070129: Swift detection of a burst
  58. GRB 070126: Swift/UVOT refined analysis
  59. GRB 070125: optical observations
  60. GRB 070126: VLT observations
  61. GRB070125: Optical observation by Kanata
  62. GRB070124: Swift-XRT Observation
  63. Possible GRB 070126: Swift/UVOT Upper Limit
  64. GRB 070125: UVOT Observations of a Fading Optical Afterglow
  65. GRB 070125: Xinglong TNT optical observations
  66. GRB070125: Swift-XRT Refined Analysis
  67. GRB 070125: SARA detection in R
  68. GRB 070125: P60 Optical Afterglow Candidate
  69. GRB 070126?: Swift detection of a possible burst
  70. GRB070125 redshift request
  71. Trigger 255685: Swift detection of a possible burst
  72. GRB070107 Swift/UVOT Observations of a Fading Optical Afterglow
  73. GRB 070110: Swift detection of a burst with a possible optical afterglow
  74. GRB 070107: Swift detection of a burst
  75. VLA observation of GRB 061222B
  76. VLA detection of GRB 061222A
  77. GRB070103: APO SPIcam i' and z' limits
  78. GRB 070103: Swift/UVOT Upper limits
  79. GRB 070103: NOT observations
  80. GRB 070103: TAROT Calern observatory optical observations
  81. erratum : SDSS Pre-burst Observations of GRB061126
  82. GRB 061210: Swift/XRT Astrometry Correction
  83. GRB 061222A: MITSuME Akeno optical upper limits
  84. GRB 061222A: Confirmation of Gemini Afterglow Candidate
  85. GRB 061222A: Xinglong Optical Limit
  86. GRB 061222A: Gemini Afterglow Candidate
  87. GRB061222A Swift/UVOT: Upper Limits
  88. GRB 061222B: Swift/UVOT Upper limits
  89. GRB 061222B: Observation with the KANATA 1.5m telescope
  90. GRB 061222A: Observation with the KANATA 1.5m telescope
  91. GRB 061222B: BOOTES-IR optical observations
  92. GRB 061222B: SARA upper limit
  93. GRB 061222B: REM NIR/optical observations
  94. GRB 061222B: TAROT La Silla observatory optical observations
  95. GRB 061222B: Swift detection of a burst
  96. GRB 061222A: Prompt ROTSE-III Optical Limits
  97. GRB 061222: Swift detection of a burst
  98. GRB 061218: TAROT La Silla observatory optical observations
  99. GRB 061217: TAROT Calern observatory optical observations
  100. GRB 061218: TORTOREM optical upper limits

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