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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"

4953 results found.

  1. GRB 090102: NOT redshift
  2. GRB 090102: Swift detection of a burst with an optical counterpart
  3. GRB 081226C: Fermi GBM detection
  4. GRB 081226: Swift detection of a possible short-hard burst
  5. GRB 080810: optical observations
  6. GRB 081223: Fermi GBM detection
  7. GRB081222 optical limit by "Pi of the Sky"
  8. GRB 081221: Gemini-N nIR imaging
  9. GRB 081221: further NOT observations
  10. GRB 081221: NOT observations
  11. IPN localization of short hard GRB 081216
  12. GRB 081203A: optical observations
  13. GRB 081203B: Suzaku WAM observation of the prompt emission
  14. GRB081203B: optical observations
  15. GRB081203A: MITSuME optical observation
  16. GRB081203A: optical observation
  17. GRB 081203A: optical observations
  18. GRB081203: optical observation
  19. GRB 081129: Fermi GBM detection
  20. GRB 081126: GRT Optical Observation
  21. GRB 081118: Fermi GBM detection.
  22. GRB 081109A: confirmation of possible detection host galaxy
  23. GRB 081102: RTT150 Optical observations
  24. GRB 081109A: Faulkes Telescope South observations
  25. GRB 081109A: Swift-XRT refined analysis
  26. GRB 081109: Swift/UVOT upper limits
  27. GRB 081109A optical upper limit
  28. GRB 081109: REM NIR afterglow detection
  29. GRB 081109: Swift detection of a burst
  30. Swift-XRT observations of GRB 081105
  31. Radio observation of GRB 080516 with ATCA
  32. Radio observation of GRB 080411 with ATCA
  33. GRB 081009: Fermi GBM detection
  34. Fermi GBM detection of additional bursts from AXP 1E1547.0-5408
  35. AXP 1E1547.0-5408 (SGR 1550-5418): Fermi GBM detection
  36. GRB 080928A: ROTSE-III Confirmation of Optical Counterpart
  37. GRB080922: A long GRB detected by INTEGRAL
  38. Trigger 324561: IGR J08408-4503 detected by Swift
  39. SGR 0501+4516: preliminary results of the Suzaku ToO observation
  40. GRB 080916B, Swift-BAT refined analysis
  41. GRB 080916B: Enhanced Swift-XRT position
  42. GRB 080916B: Swift-XRT afterglow detection
  43. GRB 080915: ROTSE-III Optical Limits
  44. SGR J0501+4516: radio pulsar searches with GBT and WSRT
  45. GRB 080903: Liverpool Telescope observations
  46. GRB 080828: SuperAGILE GRB Localization
  47. SGR 0501+4516: Decline in Activity
  48. SGR 0501+4516: GMRT Radio Observation at 618 MHz
  49. SGR 0501+4516: radio pulsar searches with GBT and WSRT
  50. GLAST Burst Monitor detection of GRB 080817
  51. GRB 080810: Liverpool Telescope observations
  52. GRB 080727B: IR photometry
  53. GRB 080727B: KAIT photometry and an early lightcurve break
  54. Trigger 317205: Swift detection of an outburst from XTE J1701-407
  55. GRB 080603A: CrAO optical observations
  56. Refined analysis of Swift Trigger 316063, is IGR J08408-4503
  57. Trigger 316063: Swift detection of a transient
  58. GRB 080701A, VATT optical upper limit
  59. GRB 080701A: Early Super-LOTIS Observations
  60. GRB 0800603A: optical observation
  61. GRB 080603B: TLS Afterglow Observation
  62. GRB 080603B : Liverpool Telescope Observations
  63. GRB 080603B: Swift-XRT refined analysis
  64. GRB 080603B: Swift/UVOT detection of the afterglow
  65. GRB 080603B, Swift-BAT refined analysis
  66. GRB080603B: RTT150 optical observations, break in light curves
  67. GRB 080603B: Swift detection of a burst with optical afterglow
  68. GRB 080603B: ROTSE-III Detection of Optical Counterpart
  69. SGR 1627-41: Chandra/RXTE/Swift Observations Scheduled
  70. GRB 080503: 2nd Epoch Chandra X-ray Observations
  71. GRB 080523, Swift-BAT refined analysis
  72. GRB 080523: Swift detection of a burst
  73. GRB080521(?): detection of possible burst from BAT slew data and XRT ToO
  74. GRB 080514B, GROND observations
  75. GRB 080506: NAYUTA Optical Observation
  76. GRB 080507: Keck photometry
  77. GRB 080503: MITSuME Ishigakijima optical upper limits
  78. GRB 080503: MITSuME Akeno optical upper limits
  79. GRB 080503: New candidate afterglow/host in Gemini imaging
  80. GRB960202B - on the association with SN 1996cr
  81. Possible GRB 080315: XRT non-detection of afterglow
  82. GRB 080413A: MOA-II optical afterglow observations
  83. GRB080330: MAGIC telescope GeV observation
  84. GRB 080330: RAPTOR detection of prompt optical flash
  85. GRB 080405: Swift-XRT position
  86. GRB 080330: REM optical observations
  87. GRB 080330, SMARTS optical/IR afterglow observations
  88. GRB 080330 Swift-UVOT refined analysis
  89. GRB 080328: Suzaku WAM observation of the prompt emission
  90. Konus-Wind observation of GRB 080328
  91. GRB 080330: GROND Observations
  92. GRB 080330: TAROT Calern observatory optical observations
  93. GRB 080330A: PAIRITEL Infrared Detections
  94. GRB 080330A: ROTSE-III Detection of Optical Counterpart
  95. GRB 080330: Swift detection of a burst with an optical counterpart
  96. GRB 080328: Swift detection of a burst with an optical counterpart
  97. GRB 080319C: UVOT Observations
  98. GRB 080319B: Gemini-South photometry
  99. GRB 080319A/B/C: INTEGRAL SPI-ACS light curves available
  100. GRB 080319b light curve by Pi-of-the-Sky

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