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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').

2983 results found.

  1. GRB 020625, optical observations
  2. GRB 020531: optical photometry of Chandra sources
  3. GRB020625 (=H2081): A Long Burst Localized by HETE
  4. GRB 020604, optical observations
  5. GRB020531: Observations with the Chandra X-ray Observatory
  6. Refined IPN error box for GRB020531
  7. IPN triangulation of the short, hard GRB020531 (=H2042)
  8. XRF 020427
  9. GRB020410: BeppoSAX NFI observations refined analysis
  10. GRB 020321: Candidate X-ray Counterparts
  11. GRB020317 : Near IR Observations from Mt Abu Observatory
  12. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  13. GRB020127: Chandra Observations and Prospective Counterparts
  14. GRB020127: Optical observations
  15. GRB 020127, I-band observations starting 3.14-hr after the event
  16. GRB010921 Optical Observations
  17. GRB011211: BeppoSAX/GRBM data
  18. GRB 011211, Optical Observations
  19. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  20. The X-ray Flash 011030 ('GRB 011030')
  21. BeppoSAX ALERT: Possible X-ray rich GRB011030
  22. GRB010928(=H1770): Localization of a Long GRB by HETE
  23. GRB 010222: HST observations -- host galaxy and late-time decay
  24. GCN and HETE status
  25. BeppoSAX/GRBM detection of GRB010728
  26. SGR1900+14: Second Burst Localized by HETE
  27. IPN triangulation of GRB010613
  28. GRB000418: HST/STIS Second-epoch Observations
  29. X-ray precursors to the large flare from SGR 1900+14
  30. SGR 1900+14 : RXTE observations
  31. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  32. GRB010412: BeppoSAX GRBM and WFC observations
  33. GRB010222: Chandra X-ray Observatory Observation
  34. GRB010222 - Optical observation
  35. GRB010222: Optical observation and decay
  36. GRB 010222 HST/Chandra TOO
  37. GRB010222: Optical Observations
  38. GRB 010220, simultaneous optical observations
  39. GRB010126 optical observations
  40. GRB001007, Radio observations
  41. GRB000926 - Amateur Optical Observations
  42. Re: GRB 000926, optical observation by Oksanen (vsnet-grb)
  43. IPN localization of GRB000801
  44. GRB 990510: Possible detection of a host galaxy
  45. GRB 990510 Host Galaxy Discovery
  46. possible optical counterpart of GRB 000630
  47. IPN annulus for GRB000620
  48. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  49. The redshift of GRB 000418
  50. Correction to IPN error box for GRB000419
  51. GRB 000408, optical observations
  52. GRB000315 [IPN Positions]
  53. GRB000226 [IPN Position]
  54. IPN error boxes for GRB991229
  55. GRB 991106, LOTIS Optical Observations
  56. GRB991105: SAX-GRBM/-WFC detection
  57. GRB 991014, radio observations
  58. GRB 991014, Optical Observations
  59. IPN/NFI error box for GRB991014
  60. GRB990907: BeppoSAX follow up and X-ray afterglow
  61. GRB990806: BATSE Observations
  62. BeppoSAX ALERT GRB990806: Summer GRB
  63. Late-time HST/STIS Observations of GRB 990510
  64. GRB 990510: BeppoSAX/GRBM observations
  65. GRB980425 Optical observations of exponential decline at late time
  66. GRB990321 REFINED IPN ANNULUS
  67. GRB990308, Possible new SGR~0209+70
  68. GRB 990123: New Constraints on Possible Foreground Galaxies
  69. GRB 990123: Continued Radio Observations
  70. GRB 981226: radio variable
  71. GRB 980613: Spectroscopy of the host galaxy
  72. GRB981226 Optical Observations
  73. GRB 981226 optical observations
  74. GRB980613 Optical Observations
  75. GRB 980613 Near-IR observations
  76. GRB 980613: Optical transient and its host galaxy
  77. GRB 980613 optical observations
  78. GRB 980519
  79. GRB980425: Radio Observations
  80. GRB980326 optical observations
  81. Untitled
  82. Untitled
  83. GRB 970828: Palomar Observations

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