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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"

4714 results found.

  1. GRB 071010 REM NIR observations
  2. GRB 071010: Swift detection of a burst
  3. Recent SGR1806-20 Activity
  4. GRB 070923: Swift detection of a short hard burst
  5. GRB920925C: search for host galaxy
  6. Candidate Orphan GRB Optical Transient in IC 4779
  7. GRB 070810A: ROTSE-III Refined Analysis
  8. Swift trigger on 4U 1700-377 while star tracker loss-of-lock
  9. GRB 070729: Swift-XRT refined analysis
  10. GRB 070729: Magellan NIR Observations
  11. GRB 070729: Swift detection of a short hard burst
  12. GRB 070724B: Swift-XRT afterglow likely candidate
  13. GRB 070724B: Swift-XRT afterglow candidates
  14. GRB 070326: Detection of first burst from BAT Slew Survey (BATSS)
  15. GRB 070714B: Keck observations
  16. GRB 070714A: Swift-BAT T_zero
  17. GRB 070714A: Swift/UVOT Upper limits
  18. GRB 070714A: Swift XRT refined analysis
  19. GRB 070714b ("Bastille"): Optical Pre-Imaging (Clarification)
  20. GRB 070714 ("Bastille"): Optical Pre-Imaging
  21. GRB 070714 : Liverpool Telescope optical counterpart ?
  22. Swift detection of a possible burst (Trigger 284850)
  23. GRB 070628 Swift-UVOT Refined Analysis
  24. GRB070616: Optical Observation by MITSuME Akeno
  25. GRB 070616, Swift-BAT partial refined analysis
  26. SWIFT J195509.6+261406 (GRB 070610): further observations
  27. GRB 070612A: Super-LOTIS observations
  28. GRB 070612A: MDM Observations
  29. GRB 070517: Gemini optical imaging
  30. GRB 070509: ROTSE-III Optical Limits
  31. GRB 070429B: ROTSE-III Optical Limits
  32. GRB 070429B: Swift detection of a short burst
  33. LT monitoring of GRB070412
  34. GRB 070411 : Planned XMM-Newton observation
  35. GRB 070318, SMARTS optical/IR afterglow observations
  36. GRB 070411: TLS data shows plateau, flares
  37. GRB 070411: Swift/UVOT observations
  38. GRB 070411: Swift-XRT refined analysis
  39. GRB 070412: Optical observations at Crni Vrh
  40. GRB 070412: IAC80 optical afterglow candidate
  41. GRB 070412: Swift detection of a burst
  42. GRB 070411: Optical observations at Crni Vrh
  43. GRB 070411: Swift detection of a burst with optical afterglow
  44. GRB 070406: Swift XRT team further analysis
  45. GRB 070406: Swift XRT Team analysis - Possible X-ray counterpart
  46. GRB 070328: Suzaku WAM observation of the prompt emission
  47. GRB 070330, SMARTS optical/IR observations
  48. GRB 070330: TAROT La Silla observatory optical observations
  49. Konus-Wind observation of GRB 070328
  50. GRB 070328: Swift detection of a burst
  51. GRB 070311, deep optical photometry
  52. Short-Hard GRB 070209: PROMPT Observations
  53. GRB 070318: Swift detection of a burst with an optical afterglow
  54. GRB 070311: Optical Brightening
  55. GRB 070311: MDM Optical Follow-up
  56. GRB 070311: MDM Optical Detection
  57. GRB 070311: MITSuME Okayama Optical Observation
  58. GRB 070311: Swift-XRT refined analysis
  59. GRB 070311: PAIRITEL confirmation of variability of REM candidate
  60. GRB 070311: REM candidate afterglow
  61. GRB 070309: A long GRB detected by INTEGRAL
  62. GRB 920925C: optical afterglow candidate
  63. GRB 070220: ART-3 Optical and NIR limits
  64. GRB 070219: ROTSE-III Optical Limits
  65. GRB 070209: Swift XRT analysis
  66. IPN localization of very bright long hard GRB 070207
  67. GRB 070209: Swift detection of a short hard burst
  68. GRB070124: Swift-XRT Follow-up Observation
  69. GRB070126: Swift-XRT Observation
  70. GRB 070125: MITSuME Okayama optical observation
  71. GRB070124: Swift-XRT Observation
  72. GRB 070110: VLT R-band photometry
  73. Further Retractions of previous Swift-BAT triggers
  74. Retractions of previous Swift-BAT triggers
  75. Konus-Wind observation of GRB 061222A
  76. GRB 061222A: Prompt ROTSE-III Optical Limits
  77. GRB 061222: Swift detection of a burst
  78. GRB 061218: TORTOREM optical upper limits
  79. GRB 061217: REM prompt observations
  80. GRB 061217: ROTSE-III Optical Limits
  81. GRB 061217: Swift detection of a short hard burst
  82. GRB 061210: MDM Follow-up Observation
  83. Swift-BAT triggers 238544 and 238546 are not GRBs
  84. GRB 061102: Swift detection of a burst
  85. GRB 061025: Gemini-S observations
  86. GRB061007: Swift UVOT followup observations
  87. GRB 061007: Magellan Spectroscopy
  88. GRB 061007: Swift XRT refined analysis
  89. GRB 061007 - FTS early brightening and power law decay
  90. GRB 061007: Swift detection of a burst with an optical counterpart
  91. GRB 061007: ROTSE-III Detection of Optical Counterpart
  92. IGR J08408-4503 (= V* LM Vel): Swift detection of a transient
  93. GRB 061002: Swift detection of a burst: CORRECTED CONTENT
  94. GRB 061002: Swift detection of a burst
  95. GRB 060923C: VLT J-band observations
  96. GRB 060923C: Keck Observations
  97. GRB 060912A: Probable Host Galaxy
  98. GRB060904b optical detections (delayed report due to internet outage)
  99. GRB 060904B: RTT150 optical observations
  100. GRB 060904B: Optical observations at Crni Vrh

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