Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! See news and announcements

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"

23584 results found.

  1. GRB 070224: SARA upper limit
  2. GRB 070224, Swift-BAT refined analysis
  3. GRB 070224: Swift detection of a burst
  4. RHESSI Spectrum of GRB070220
  5. GRB 070223: Optical-IR observation with KANATA
  6. GRB 070223, Swift-BAT refined analysis
  7. GRB070223 - SDSS Pre-Burst Observations
  8. GRB 070223: Liverpool Telescope Possible Afterglow Candidate
  9. GRB070223: Swift burst
  10. Konus-Wind and Konus-A observations of GRB 070220
  11. GRB 070220: MITSuME Okayama Optical Observation
  12. GRB 070220: ART-3 Optical and NIR limits
  13. GRB 070220 Swift-BAT Refined Analysis
  14. Swift/UVOT refined analysis of GRB070220
  15. GRB 070209: Swift XRT refined analysis
  16. GRB 070220: Swift-XRT Refined Analysis
  17. GRB 070220: Observation with the KANATA 1.5m telescope
  18. GRB 070220 : Faulkes Telescope North optical limit
  19. GRB 070220: Swift detection of a burst
  20. GRB 070219: XRT Refined Analysis
  21. GRB 070219: I-band observations
  22. GRB 070219, Swift-BAT refined analysis
  23. GRB 070219: optical TNG observations
  24. GRB 070219: Liverpool Telescope Observations
  25. GRB 070219: ROTSE-III Optical Limits
  26. GRB070219 - SDSS Pre-Burst Observations
  27. GRB 070219: Swift detection of a burst
  28. Swift-BAT trigger 260304 is NOT a burst or transient
  29. GRB 060927: PROMPT Observations
  30. GRB 070125: Break in Optical Decay
  31. GRB 070209: Swift XRT analysis
  32. GRB 070208: MARGE Optical Observations
  33. IPN localization of very bright long hard GRB 070207
  34. IPN localization of very intense short GRB 070201
  35. GRB 070209, Swift-BAT refined analysis of the short hard burst
  36. GRB 070209: Swift detection of a short hard burst
  37. GRB 070208: Swift XRT refined analysis
  38. GRB 070208, Swift-BAT refined analysis
  39. GRB070208 - SDSS Pre-Burst Observations
  40. GRB070208: Faulkes Telescope North Afterglow Identification
  41. GRB 070208: Swift detection of a burst
  42. GRB 070125 detection with CARMA
  43. GRB 070129: Swift/UVOT Upper limits
  44. GRB061217: MAGIC telescope GeV observation
  45. GRB 070129, Swift-BAT refined analysis of a particularly long
  46. GRB 070129: VLT observations
  47. GRB 070129: Swift detection of a burst
  48. GRB 070125: MITSuME Okayama optical observation
  49. GRB 070125: AAVSO optical observations
  50. GRB 070125: PROMPT detections
  51. GRB 070124: Suzaku WAM observation of the prompt emissions
  52. GRB 070125: UVOT Detection in Ultraviolet Filters
  53. GRB 070126, Swift-BAT refined analysis of a very faint burst
  54. GRB070125: Optical observation by Kanata
  55. GRB070124: Swift-XRT Observation
  56. GRB 070126?: Swift detection of a possible burst
  57. RHESSI Spectrum of GRB070125
  58. IPN-BAT localization of GRB070125 (very long duration, intense)
  59. Konus-Wind observation of short hard GRB 070124
  60. IPN localization of GRB070124 (short duration, hard spectrum)
  61. GRB 070110: Continued Detection and Request for Ground Followup
  62. GRB 050904: Second Epoch of HST/NICMOS Observations
  63. GRB 070110: Ep,i - Eiso correlation
  64. GRB 070107: Suzaku WAM observation of the prompt emission
  65. GRB 070110 declared a "Burst of Interest" by Swift team
  66. Swift-BAT Trigger 255685 is not a GRB
  67. Trigger 255685: Swift detection of a possible burst
  68. GRB070110: Swift XRT Team refined analysis
  69. GRB 070110, Swift-BAT refined analysis
  70. GRB 070110: Swift detection of a burst with a possible optical afterglow
  71. GRB 070107: Possible UVOT Afterglow
  72. GRB 070107, Swift-BAT refined analysis
  73. GRB 070107: Swift/XRT position
  74. GRB 070107: Swift detection of a burst
  75. GRB070103: APO SPIcam i' and z' limits
  76. GRB 061201: Nearby Galaxy Cluster Abell 995 is at z=0.0865
  77. GRB070103: KPNO 4m+FLAMINGOS J limit
  78. GRB 070103, Swift-BAT refined analysis
  79. GRB 070103: TAROT Calern observatory optical observations
  80. GRB 070103: Swift detection of a burst
  81. Konus-Wind observation of GRB 061222A
  82. GRB 061210: Swift/XRT Astrometry Correction
  83. GRB 061222B: TAROT La Silla observatory early optical observations
  84. GRB 061218: TAROT La Silla observatory early optical observations
  85. GRB 061222B, Swift-BAT refined analysis
  86. GRB 061222B: Observation with the KANATA 1.5m telescope
  87. GRB 061222A: Observation with the KANATA 1.5m telescope
  88. GRB 061222B: BOOTES-IR optical observations
  89. GRB 061222A, Swift-BAT refined analysis
  90. GRB 061222B: TAROT La Silla observatory afterglow observation
  91. GRB 061222B: TAROT La Silla observatory optical observations
  92. GRB 061222B: Swift detection of a burst
  93. GRB 061222: Swift detection of a burst
  94. GRB 061217: Astrometry-Corrected XRT Position
  95. GRB 061217: Confirmation of host candidate
  96. GRB 061217: Extended object in the revised XRT error circle
  97. GRB 061217, Candidate host galaxy
  98. GRB 061210: Possible Host Galaxy (S2-G2) Keck Spectrum
  99. GRB 061201: Magellan Redshift of nearby Abell cluster
  100. GRB 061218: TAROT La Silla observatory optical observations

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Looking for U.S. government information and services? Visit USA.gov