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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"

28704 results found.

  1. GRB981220 I-band Observations
  2. GRB 981220
  3. GRB 981220 Optical Observations
  4. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  5. BeppoSAX NFI Observation of GRB980425
  6. GRB980425 Optical Follow-up
  7. GRB980425: X-ray revised positions
  8. GRB980703 Very Long Baseline Interferometry
  9. GRB970508 optical observations
  10. Optical Observations of the Host Galaxy of GRB 980519
  11. GRB980519, Optical Observations
  12. GRB980703, Host galaxy multicolor photometry
  13. GRB 980703 (NFI observations)
  14. GRB980703 optical photometry
  15. GRB 980703: BATSE Observations
  16. GRB980703 optical observations
  17. GRB980703: Radio transient
  18. GRB980703 H-band Observations
  19. GRB 980703: Spectrum of the proposed optical counterpart
  20. RXTE Observation of GRB 980706
  21. GRB980703: Spectrum of the proposed optical counterpart
  22. GRB980703 Transient Optical Follow-Up
  23. GRB980703: LOTIS observation at early times
  24. GRB980613 Optical Observations
  25. GRB 980703
  26. GRB980703 (I band observations)
  27. GRB 980703 H-band Observations
  28. GRB980703: radio source/optical transient
  29. BeppoSAX NFI observations of GRB 980703
  30. GRB980519 observation report
  31. Radio observations of SGRs
  32. GRB 980613 Near-IR observations
  33. GRB980613, optical observations
  34. GRB 980613: Optical transient and its host galaxy
  35. SGR1627-41, RXTE/ASM observations
  36. SGR1627-41, Refined IPN annulus location
  37. GRB 980613: Detection of the probable host galaxy
  38. Reduced error box of SGR 1627-41
  39. SGR1627-41, BeppoSAX-GRBM detections
  40. GRB 980613 Optical Observations
  41. GRB 980613 optical observations
  42. GRB980613 Optical Observations
  43. GRB980613 observations from Palomar
  44. GRB 980613 new optical/IR observations
  45. GRB971214 Secondary Standards
  46. GRB980519 Secondary Standards
  47. SGR1900+14
  48. GRB 980519 Optical Observations
  49. GRB980519 optical observations
  50. GRB980519 I-band observations
  51. GRB 980519
  52. GRB980519 optical observations
  53. GRB 980519 Optical Observations
  54. GRB980519 BATSE Observations
  55. GRB970519, optical follow-up at Schmidt Calern
  56. GRB980519 optical observations
  57. GRB980519 Optical Observations
  58. GRB980519 Optical Observations
  59. GRB980519 IPN POSITION
  60. GRB980519 Optical Observations
  61. GRB 980519 Optical Observations
  62. GRB980519 optical observations
  63. GRB980515, BeppoSAX IAUC to be submitted
  64. GRB980519, BeppoSAX-WFC updated position
  65. GRB 980425 Radio Light Curve
  66. GRB 980425 Brightness Temperature
  67. BSAX Observations of GRB980425 field
  68. IPN web site of GRBs
  69. GRB980425 BATSE observations
  70. SAX J0840.7+2248 Optical Observations
  71. GRB 980425 optical observations
  72. GRB980425: optical obs.
  73. GRB980425: Radio Observations
  74. GRB 980425 optical observations
  75. GRB980326, optical observations
  76. GRB980326, optical observations
  77. GRB980329, Fading IR counterpart to radio source
  78. GRByymmdd, Announcement of automation
  79. GRB980326 IPN annulus
  80. GRB980329
  81. GRB980329 Keck K-band observations
  82. GRB980329 sub-millimeter observations
  83. GRB980329 IPN annulus
  84. GRB980329 optical observations
  85. GRB980329 near-IR observations
  86. GRB980329 optical observations
  87. GRB980326 optical observations
  88. GRB980326 optical observations
  89. GRB970508 SAO RAS optical observations
  90. GRB 971214: Redshift from Keck Observations
  91. Near-IR follow-up on GRB 971227
  92. GRB971214: Keck R & I-band Observations
  93. GRB 971227: Optical Observations
  94. Optical Observations of the GRB 971227 field
  95. GRB971227: Plaskett R-band observations
  96. GRB 971227: Optical clarifications
  97. GRB971227: LOTIS observations
  98. GRB971214: Optical Observations and Calibrations
  99. Optical Observations of GRB 971214 at Keck
  100. GRB 971024: Refined analysis by USNOFS Observations

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