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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 080916B, Swift-BAT refined analysis
  2. GRB 080916B: Enhanced Swift-XRT position
  3. GRB 080916B: Swift-XRT afterglow detection
  4. GRB 080915: ROTSE-III Optical Limits
  5. SGR J0501+4516: radio pulsar searches with GBT and WSRT
  6. GRB 080903: Liverpool Telescope observations
  7. GRB 080828: SuperAGILE GRB Localization
  8. SGR 0501+4516: Decline in Activity
  9. SGR 0501+4516: GMRT Radio Observation at 618 MHz
  10. SGR 0501+4516: radio pulsar searches with GBT and WSRT
  11. GLAST Burst Monitor detection of GRB 080817
  12. GRB 080810: Liverpool Telescope observations
  13. GRB 080727B: IR photometry
  14. GRB 080727B: KAIT photometry and an early lightcurve break
  15. Trigger 317205: Swift detection of an outburst from XTE J1701-407
  16. GRB 080603A: CrAO optical observations
  17. Refined analysis of Swift Trigger 316063, is IGR J08408-4503
  18. Trigger 316063: Swift detection of a transient
  19. GRB 080701A, VATT optical upper limit
  20. GRB 080701A: Early Super-LOTIS Observations
  21. GRB 0800603A: optical observation
  22. GRB 080603B: TLS Afterglow Observation
  23. GRB 080603B : Liverpool Telescope Observations
  24. GRB 080603B: Swift-XRT refined analysis
  25. GRB 080603B: Swift/UVOT detection of the afterglow
  26. GRB 080603B, Swift-BAT refined analysis
  27. GRB080603B: RTT150 optical observations, break in light curves
  28. GRB 080603B: Swift detection of a burst with optical afterglow
  29. GRB 080603B: ROTSE-III Detection of Optical Counterpart
  30. SGR 1627-41: Chandra/RXTE/Swift Observations Scheduled
  31. GRB 080503: 2nd Epoch Chandra X-ray Observations
  32. GRB 080523, Swift-BAT refined analysis
  33. GRB 080523: Swift detection of a burst
  34. GRB080521(?): detection of possible burst from BAT slew data and XRT ToO
  35. GRB 080514B, GROND observations
  36. GRB 080506: NAYUTA Optical Observation
  37. GRB 080507: Keck photometry
  38. GRB 080503: MITSuME Ishigakijima optical upper limits
  39. GRB 080503: MITSuME Akeno optical upper limits
  40. GRB 080503: New candidate afterglow/host in Gemini imaging
  41. GRB960202B - on the association with SN 1996cr
  42. Possible GRB 080315: XRT non-detection of afterglow
  43. GRB 080413A: MOA-II optical afterglow observations
  44. GRB080330: MAGIC telescope GeV observation
  45. GRB 080330: RAPTOR detection of prompt optical flash
  46. GRB 080405: Swift-XRT position
  47. GRB 080330: REM optical observations
  48. GRB 080330, SMARTS optical/IR afterglow observations
  49. GRB 080330 Swift-UVOT refined analysis
  50. GRB 080328: Suzaku WAM observation of the prompt emission
  51. Konus-Wind observation of GRB 080328
  52. GRB 080330: GROND Observations
  53. GRB 080330: TAROT Calern observatory optical observations
  54. GRB 080330A: PAIRITEL Infrared Detections
  55. GRB 080330A: ROTSE-III Detection of Optical Counterpart
  56. GRB 080330: Swift detection of a burst with an optical counterpart
  57. GRB 080328: Swift detection of a burst with an optical counterpart
  58. GRB 080319C: UVOT Observations
  59. GRB 080319B: Gemini-South photometry
  60. GRB 080319A/B/C: INTEGRAL SPI-ACS light curves available
  61. GRB 080319b light curve by Pi-of-the-Sky
  62. GRB 080319b: Early IR Imaging from PAIRITEL
  63. Swift Trigger 306745 is not a GRB
  64. GRB 080315: TAROT Calern observatory optical observations
  65. GRB 080310: ROTSE-III Observations of Optical Counterpart
  66. GRB080310: Optical observation by MITSuME telescope
  67. GRB 080310: PAIRITEL detection and PAIRITEL+KAIT+UVOT SED
  68. GRB 080310: Swift-XRT refined analysis
  69. GRB 080310: RRM optical photometry with the VLT
  70. GRB080310: Super-LOTIS suggestion of brightening
  71. GRB 080310, SMARTS optical/IR afterglow observations
  72. GRB080229, optical upper limit (Correction)
  73. GRB080229, optical upper limit
  74. GRB 080307: Early RAPTOR Limits
  75. GRB080307: Optical upper limits
  76. GRB 080303: REM NIR afterglow candidate
  77. ESO optical and NIR observations of GRB 080218B
  78. GRB 080218b, SMARTS optical/IR limits
  79. GRB 080121: Upper limit on X-ray afterglow
  80. GRB 071227: optical afterglow
  81. GRB 071227: Magellan observations
  82. GRB071227: Swift/UVOT refined analysis
  83. GRB 071129: Swift detection of a burst
  84. GRB 071122: Swift detection of a burst
  85. GRB071118 MITSuME OAO optical observation
  86. GRB071109: Super-LOTIS observations
  87. GRB071010b: optical observation
  88. GRB0711101: Two new source from Xinglong TNT observation
  89. GRB 071101: a nearby galaxy
  90. GRB 071031: Swift-XRT Team refined analysis
  91. GRB 071031: GROND detection in all bands
  92. GRB 071031: Swift detection of a burst with an optical counterpart
  93. GRB 071025: Kuiper Telescope Optical Observations
  94. GRB071021: MITSuME Okayama Optical Upper Limits
  95. GRB 071020: Swift-XRT refined analysis
  96. GRB 071020: Swift detection of a bright burst
  97. GRB 071013: TNT optical data refined analysis
  98. GRB 071010B correction to GCN 6892 optical observations
  99. GRB 071010B optical photometry
  100. GRB 071011: Optical afterglow candidate

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