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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"

24595 results found.

  1. Optical Observations of GRB981226
  2. GRB 981220:Optical Observations
  3. GRB 981226 optical observations
  4. GRB 981220
  5. GRB 981220, radio observations
  6. GRB981220 I-band Observations
  7. GRB 981220
  8. GRB 980326/Host Galaxy
  9. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  10. BeppoSAX NFI Observation of GRB980425
  11. GRB980329 R,I flux calibration and R,I,K upper limits
  12. GRB980425 Optical Follow-up
  13. GRB 980923 BATSE Observations
  14. SGR1900+14, BeppoSAX-GRBM observations
  15. GRB970508 optical observations
  16. GRB971214, association with a Galactic star?
  17. GRB980519, Optical Observations
  18. GRB980703 - BeppoSAX/GRBM detection
  19. GRB980703 optical photometry
  20. GRB 980703: BATSE Observations
  21. GRB980703 optical observations
  22. GRB980703: Radio transient
  23. GRB 980703: Spectrum of the proposed optical counterpart
  24. GRB980703 Transient Optical Follow-Up
  25. GRB980703: LOTIS observation at early times
  26. GRB980613 Optical Observations
  27. GRB980703 (I band observations)
  28. BeppoSAX NFI observations of GRB 980703
  29. GRB980519 observation report
  30. GRB980703 optical followup
  31. Radio observations of SGRs
  32. SGR1900+14 field optical observations
  33. GRB980613, optical observations
  34. GRB 980613: Optical transient and its host galaxy
  35. SGR1627-41, RXTE/ASM observations
  36. GRB 980613: Detection of the probable host galaxy
  37. Reduced error box of SGR 1627-41
  38. GRB 980613: BATSE Observations
  39. GRB 980613 Optical Observations
  40. GRB 980613 optical observations
  41. Discovery of a new SGR source, SGR1627-41
  42. GRB980613 Optical Observations
  43. GRB980613 observations from Palomar
  44. GRB 980613 optical/IR obs.
  45. GRB980613 Near Infra-Red Observations
  46. GRB971214 Secondary Standards
  47. GRB980519 Secondary Standards
  48. BATSE on-board GRB trigger change
  49. GRB 980519 Optical Observations
  50. GRB 980519
  51. GRB980519 optical observations
  52. GRB 980519 Optical Observations
  53. GRB980519 BATSE Observations
  54. GRB980519 Optical Observations
  55. GRB980519 Optical Observations
  56. GRB 980519 Optical Observations
  57. GRB980515, BeppoSAX IAUC to be submitted
  58. BSAX Observations of GRB980425 field
  59. IPN web site of GRBs
  60. GRB980425 BATSE observations
  61. SAX J0840.7+2248 Optical Observations
  62. GRB980425: optical obs.
  63. GRB980425: Radio Observations
  64. report on BSAX observations of GRB980425
  65. GRB 980329 ROSAT observation
  66. GRB980326 X-ray Observations
  67. GRB980326, optical observations
  68. GRB980326, optical observations
  69. GRB980329, Fading IR counterpart to radio source
  70. GRB980329 Keck K-band observations
  71. GRB980329 sub-millimeter observations
  72. GRB980329 optical observations
  73. GRB980329 near-IR observations
  74. GRB980329 near-IR observations
  75. GRB980326 optical observations
  76. GRB980329 optical observations
  77. GRB980329 VLA observations
  78. GRB980329 optical observations
  79. GRB980329 optical observations
  80. GRB980326 optical observations
  81. GRB980326 optical observations
  82. Optical Observations of GRB 970508
  83. Near-IR follow-up on GRB 971227
  84. Optical Observations of the GRB 971227 field
  85. Optical Observations on GRB 971227
  86. GRB971227: Plaskett R-band observations
  87. GRB 971227: Optical clarifications
  88. GRB971227: Further CAHA R-band images
  89. GRB971227: LOTIS observations
  90. GRB971214: Optical Observations and Calibrations
  91. GRB 971214: Optical Observations
  92. Radio Observations of GRB 971214 at the VLA
  93. GRB 971024: Refined analysis by USNOFS Observations
  94. GRB 971024: KPNO Optical Observations
  95. GRB 970828: Palomar Observations

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