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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"

24896 results found.

  1. IPN triangulation of GRB021205 (large error box)
  2. GRB021201, BVRcIc field photometry
  3. GRB 021201: BOOTES simultaneous optical observations
  4. IPN triangulation of GRB021201 (short/hard burst, small error box)
  5. GRB021004, late time optical observations
  6. GRB021004 Chandra Observation
  7. IPN detection of continued SGR1900+14 activity
  8. Improved IPN error box for GRB021125
  9. IPN BURST POSITION
  10. IPN triangulation of GRB021125 (INTEGRAL BURST)
  11. GRB021125 : A long GRB localized by INTEGRAL
  12. IPN confirmation of the reactivation of SGR1900+14
  13. GRB021113, SPI ACS observation
  14. GRB 021112: Afterglow or Variable Star?
  15. GRB021113: optical observations at Bisei
  16. GRB 021113: Evidence for a Dark Optical Afterglow
  17. GRB021112, BVRI field photometry
  18. GRB 021112: Variable Source in R-band search
  19. GRB021112: Optical Observations
  20. IPN triangulation of GRB021113 (=H2449; annulus)
  21. GRB 021113: Optical observations
  22. GRB 021112: RAPTOR Observations
  23. GRB021113 (=H2449): A Long GRB Localized by HETE
  24. GRB021112 (=H2448): A Long GRB Localized by HETE
  25. GRB 021016: Optical Observations
  26. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  27. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  28. SGR1900+14 activity, November 2-4, 2002
  29. GRB021104: optical observations
  30. Detection of activity from SGR 1900+14 with the RXTE/PCA
  31. IPN triangulation of GRB021027 (single large error box)
  32. IPN triangulation of GRB021027 (two large error boxes)
  33. GRB 021023: Curious K-band Source(s) Just Outside of IPN Localization
  34. GRB 021004: optical observations
  35. IPN triangulation of GRB021023 (small error boc)
  36. GRB 020813; likely host galaxy.
  37. IPN triangulation of GRB021020 (smaller error box)
  38. IPN triangulation of GRB021020
  39. GRB 021008, optical observations
  40. IPN triangulation of GRB021016 (small error box)
  41. IPN triangulation of GRB021014 (large error box)
  42. IPN triangulation of GRB021013 (single error box)
  43. GRB 021004: optical spectroscopy on Oct 11
  44. IPN triangulation of GRB021013 (two small error boxes)
  45. GRB021004: High-resolution optical spectroscopy
  46. XRF 020903: flattening of the optical light curve.
  47. GRB021004, UBVRcIc field photometry update
  48. IPN triangulation of GRB021008 (single error box)
  49. GRB 021004 submm observations
  50. IPN triangulation of GRB021008 (two small error boxes)
  51. GRB021004 Chandra HETG Observations
  52. GRB 021004: Optical/NIR Observations
  53. GRB 021004: Additional V-band Polarimetric Observations
  54. GRB021004: optical observation
  55. GRB 021004: Host Galaxy Star Formation Rate
  56. GRB 021004 submm observations
  57. GRB 021004: WC wind?
  58. GRB021004: NIR and Optical observations
  59. GRB 021004: Optical observations, AUDE network
  60. GRB 021004 - VLA Radio Observations
  61. GRB 021004 - Unusual Radio-to-Submm Spectrum
  62. GRB 021004: optical spectroscopy
  63. IPN triangulation of GRB021007 (annulus)
  64. GRB021004: optical observations and predicted break time
  65. GRB021004: BVRc photometry
  66. GRB021004 radio observation
  67. HETE fluences for GRB021004
  68. GRB 021004: Optical Photometry at 2.5 Days
  69. GRB 021004: polarimetric observations
  70. GRB 021004: V-band Polarimetric Observations
  71. GRB021004: Update Bisei photometric data
  72. IRAM Millimeter detection of GRB 021004
  73. GRB 021004 radio observation
  74. GRB 021004: Optical Photometry at 1.5 Days
  75. GRB021004, BVRcIc field photometry
  76. GRB021004: Optical Spectroscopy
  77. GRB 021004 radio search
  78. XRF020903, BVRI field photometry
  79. XRF020903: TNG and Asiago photometry
  80. GRB 020903: Optical observations at RIKEN
  81. XRF 020903: Correction to GCN 1560
  82. XRF 020903: VRI observations
  83. XRF 020903: R band observations
  84. XRF 020903: Archival Optical Images
  85. Radio Observations of XRF 020903: The Missing Link
  86. XRF 020903: Supernova
  87. IPN triangulation of GRB020923 (two error boxes)
  88. IPN triangulation of GRB020914B
  89. IPN triangulation of GRB020911 (2 large error boxes)
  90. GRB 020305: HST/STIS observations
  91. Confirmation of IPN error box for GRB020910
  92. IPN triangulation of GRB020910
  93. IPN GCN Circulars now to be issued without restriction
  94. Single IPN error box for GRB020904
  95. XRF 020903: optical observation at Kyoto
  96. GRB020322 : HST/STIS observations
  97. XRF 020903: Optical observations
  98. IPN triangulation of GRB020904
  99. INTEGRAL GRBs added to GCN
  100. SGR1900+14 burst localized by HETE

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