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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"

24878 results found.

  1. GRB021112: Optical Observations
  2. IPN triangulation of GRB021113 (=H2449; annulus)
  3. GRB 021113: Optical observations
  4. GRB 021112: RAPTOR Observations
  5. GRB021113 (=H2449): A Long GRB Localized by HETE
  6. GRB021112 (=H2448): A Long GRB Localized by HETE
  7. GRB 021016: Optical Observations
  8. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  9. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  10. SGR1900+14 activity, November 2-4, 2002
  11. GRB021104: optical observations
  12. Detection of activity from SGR 1900+14 with the RXTE/PCA
  13. IPN triangulation of GRB021027 (single large error box)
  14. IPN triangulation of GRB021027 (two large error boxes)
  15. GRB 021023: Curious K-band Source(s) Just Outside of IPN Localization
  16. GRB 021004: optical observations
  17. IPN triangulation of GRB021023 (small error boc)
  18. GRB 020813; likely host galaxy.
  19. IPN triangulation of GRB021020 (smaller error box)
  20. IPN triangulation of GRB021020
  21. GRB 021008, optical observations
  22. IPN triangulation of GRB021016 (small error box)
  23. IPN triangulation of GRB021014 (large error box)
  24. IPN triangulation of GRB021013 (single error box)
  25. GRB 021004: optical spectroscopy on Oct 11
  26. IPN triangulation of GRB021013 (two small error boxes)
  27. GRB021004: High-resolution optical spectroscopy
  28. XRF 020903: flattening of the optical light curve.
  29. GRB021004, UBVRcIc field photometry update
  30. IPN triangulation of GRB021008 (single error box)
  31. GRB 021004 submm observations
  32. IPN triangulation of GRB021008 (two small error boxes)
  33. GRB021004 Chandra HETG Observations
  34. GRB 021004: Optical/NIR Observations
  35. GRB 021004: Additional V-band Polarimetric Observations
  36. GRB021004: optical observation
  37. GRB 021004: Host Galaxy Star Formation Rate
  38. GRB 021004 submm observations
  39. GRB 021004: WC wind?
  40. GRB021004: NIR and Optical observations
  41. GRB 021004: Optical observations, AUDE network
  42. GRB 021004 - VLA Radio Observations
  43. GRB 021004 - Unusual Radio-to-Submm Spectrum
  44. GRB 021004: optical spectroscopy
  45. IPN triangulation of GRB021007 (annulus)
  46. GRB021004: optical observations and predicted break time
  47. GRB021004: BVRc photometry
  48. GRB021004 radio observation
  49. HETE fluences for GRB021004
  50. GRB 021004: Optical Photometry at 2.5 Days
  51. GRB 021004: polarimetric observations
  52. GRB 021004: V-band Polarimetric Observations
  53. GRB021004: Update Bisei photometric data
  54. IRAM Millimeter detection of GRB 021004
  55. GRB 021004 radio observation
  56. GRB 021004: Optical Photometry at 1.5 Days
  57. GRB021004, BVRcIc field photometry
  58. GRB021004: Optical Spectroscopy
  59. GRB 021004 radio search
  60. XRF020903, BVRI field photometry
  61. XRF020903: TNG and Asiago photometry
  62. GRB 020903: Optical observations at RIKEN
  63. XRF 020903: Correction to GCN 1560
  64. XRF 020903: VRI observations
  65. XRF 020903: R band observations
  66. XRF 020903: Archival Optical Images
  67. Radio Observations of XRF 020903: The Missing Link
  68. XRF 020903: Supernova
  69. IPN triangulation of GRB020923 (two error boxes)
  70. IPN triangulation of GRB020914B
  71. IPN triangulation of GRB020911 (2 large error boxes)
  72. GRB 020305: HST/STIS observations
  73. Confirmation of IPN error box for GRB020910
  74. IPN triangulation of GRB020910
  75. IPN GCN Circulars now to be issued without restriction
  76. Single IPN error box for GRB020904
  77. XRF 020903: optical observation at Kyoto
  78. GRB020322 : HST/STIS observations
  79. XRF 020903: Optical observations
  80. IPN triangulation of GRB020904
  81. INTEGRAL GRBs added to GCN
  82. SGR1900+14 burst localized by HETE
  83. GRB020813: High-resolution optical spectroscopy
  84. GRB020812: negative optical observations
  85. GRB 020812: optical observation at Kyoto University
  86. Second epoch K band imaging of GRB 020819
  87. GRB 020813 : HST observations
  88. GRB 020812: early time optical observation at Ouda Station
  89. GRB020813: Magellan BVRI Photometry
  90. GRB 020819: Optical observations
  91. K band observation of GRB 020819
  92. GRB020813: optical and NIR observations
  93. GRB020813: Fading X-ray Afterglow Observed with Chandra
  94. GRB020813, UBVRI field calibration
  95. GRB020812: NIR observations
  96. Polarimetry of GRB020813: evidence for variability
  97. GRB020813 IRAM millimeter observations
  98. GRB020812: optical observations
  99. GRB020813: High-Resolution Optical Observations
  100. GRB 020812: optical observation at Bisei

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