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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"

34221 results found.

  1. GRB971214, association with a Galactic star?
  2. Optical Observations of the Host Galaxy of GRB 980519
  3. GRB980519, Optical Observations
  4. GRB980703, Host galaxy multicolor photometry
  5. GRB980703 - BeppoSAX/GRBM detection
  6. GRB 980703 (NFI observations)
  7. GRB980703 optical photometry
  8. GRB 980703: BATSE Observations
  9. GRB980703: Radio transient
  10. GRB980703 H-band Observations
  11. GRB 980703: Spectrum of the proposed optical counterpart
  12. RXTE Observation of GRB 980706
  13. GRB980703: Spectrum of the proposed optical counterpart
  14. GRB980703 Transient Optical Follow-Up
  15. GRB980703: LOTIS observation at early times
  16. GRB980613 Optical Observations
  17. GRB 980703
  18. GRB 980703 H-band Observations
  19. GRB980703 (optical R observations)
  20. GRB980706
  21. GRB980703: radio source/optical transient
  22. BeppoSAX NFI observations of GRB 980703
  23. GRB 980703: ASM Position & Intensity
  24. GRB980703
  25. GRB980703 optical followup
  26. GRB 980613 Near-IR observations
  27. GRB980613, optical observations
  28. GRB 980613: Optical transient and its host galaxy
  29. GRB 980613: Detection of the probable host galaxy
  30. GRB 980613: BATSE Observations
  31. GRB 980613 Optical Observations
  32. GRB 980613 optical observations
  33. GRB980613 Optical Observations
  34. GRB980613 observations from Palomar
  35. GRB980613 BeppoSAX-NFI follow up
  36. GRB 980613 new optical/IR observations
  37. GRB 980613 optical/IR obs.
  38. GRB980613 Near Infra-Red Observations
  39. GRB980611
  40. GRB980613, BeppoSAX WFC positions
  41. GRB971214 Secondary Standards
  42. GRB980519 Secondary Standards
  43. BATSE on-board GRB trigger change
  44. GRB 980519 Optical Observations
  45. GRB980519 optical observations
  46. GRB 980519
  47. GRB980519 optical observations
  48. GRB 980519 Optical Observations
  49. GRB980519 BATSE Observations
  50. GRB970519, optical follow-up at Schmidt Calern
  51. GRB980519 optical observations
  52. GRB980519 Optical Observations
  53. GRB980519 Optical Observations
  54. GRB980519 IPN POSITION
  55. GRB980519 Optical Observations
  56. GRB 980519 Optical Observations
  57. GRB980519 optical observations
  58. GRB980515, BeppoSAX IAUC to be submitted
  59. BATSE on-board GRB trigger change
  60. BeppoSAX GRB ALERT: updated position of grb980515
  61. GRB 980425 Radio Light Curve
  62. GRB 980425 Brightness Temperature
  63. GRB980425 BATSE observations
  64. SAX J0840.7+2248 Optical Observations
  65. GRB 980425 optical observations
  66. GRB980425: optical obs.
  67. GRB980425: Radio Observations
  68. GRB 980425 optical observations
  69. GRB 980425 optical observations
  70. GRB 980329 ROSAT observation
  71. GRB980326 X-ray Observations
  72. GRB980326, optical observations
  73. GRB980326, optical observations
  74. GRB980329, Fading IR counterpart to radio source
  75. GRByymmdd, Announcement of automation
  76. GRB980326 IPN annulus
  77. GRB980329 sub-millimeter observations
  78. GRB980329 IPN annulus
  79. GRB980329 near-IR observations
  80. GRB980326 optical observations
  81. GRB980329 optical observations
  82. GRB980329 VLA observations
  83. GRB980329 near IR observations
  84. GRB980329 optical observations
  85. GRB980329 optical observations
  86. GRB980326 optical observations
  87. GRB980326 optical observations
  88. GRB970508 SAO RAS optical observations
  89. Optical Observations of GRB 970508
  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. Optical Observations on GRB 971227
  96. GRB971227: Plaskett R-band observations
  97. GRB 971227: Optical clarifications
  98. Optical Observations for GRB 971227
  99. GRB971227: Further CAHA R-band images
  100. GRB971227: LOTIS observations

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