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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"

37202 results found.

  1. GRB 990510 Host Galaxy Discovery
  2. GRB 000727, optical observations
  3. IPN localization of GRB000727
  4. GRB 990705, HST/STIS observations of the host galaxy
  5. GRB 990712: Late time HST/STIS Observations
  6. GRB 991216, HST/STIS observations
  7. GRB981226, HST/STIS observations of the host galaxy
  8. GRB 000630: Detection of the Optical Afterglow
  9. GRB000630, Revised BVRI Field Photometry
  10. GRB000630, Optical Observations
  11. GRB000630, optical observations
  12. GRB000630, BVRI Field Photometry
  13. GRB000630, optical observations
  14. GRB000630: Optical observations
  15. possible optical counterpart of GRB 000630
  16. IPN triangulation of GRB000630
  17. GRB 000623, optical observations
  18. GRB 000620, optical observations
  19. GRB000418, HST/STIS Observations
  20. GRB990123: Late-time HST/STIS observations of the host
  21. GRB 990506, HST/STIS Observations of the Host Galaxy
  22. GRB000623
  23. GRB 000620: J-band observations
  24. GRB990308, HST/STIS observations of the host galaxy
  25. IPN annulus for GRB000620
  26. GRB000615, Radio observations
  27. GRB000607, optical observations
  28. GRB 000615: NIR further observations
  29. BeppoSAX ALERT: GRB000620
  30. GRB000620: BeppoSAX Alert
  31. GRB990123, HST/STIS observations of the host galaxy
  32. GRB 000615, near-infrared observations
  33. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  34. GRB000616 [IPN Position]
  35. GRB000615B [IPN Position]
  36. GRB000615, further R-band photometry
  37. GRB 000615: NIR observations
  38. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  39. GRB000615, R-band photometry
  40. GRB980425, HST/STIS observations of the host galaxy
  41. GRB000615: BeppoSAX GRB Alert
  42. The Hosts of GRB 980703 and GRB 971214
  43. GRB 000301C: Further Late-Time HST/STIS observations
  44. GRB000528: follow-up X-ray measurements and update of IPN annulus
  45. GRB980519, HST/STIS observations of the host galaxy
  46. GRB000607, Radio Observations
  47. GRB000604 - Optical observations
  48. GRB000607, A SHORT, HARD BURST
  49. GRB000604, optical observations
  50. GRB000528, optical observations at ESO
  51. GRB 000604 optical observations
  52. GRB 000418: Detection of the Host Galaxy
  53. GRB000604, optical observations, comparison with DPOSS
  54. GRB000604 [IPN Position]
  55. X-ray Afterglow of GRB 000529
  56. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  57. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  58. IPN localization and time history of GRB000528
  59. New IPN localization of GRB000529
  60. GRB 000528 - WFC measurements
  61. GRB000528: BeppoSAX GRBM observations
  62. GRB 000528 Optical Observations
  63. GRB000519, BVRI field photometry
  64. IPN triangulation of GRB000519
  65. IPN triangulation of GRB000516
  66. Re: GRB000508B : Optical observations
  67. GRB 000418, Optical observation
  68. GRB000508B, optical photometry
  69. GRB000508B, BVR field photometry
  70. Possible GRB-related phenomenon
  71. RXTE/ASM and IPN localization of GRB 000508B
  72. GRB000424, UBVRI field photometry
  73. GRB 000424 Optical Observations
  74. GRB000418, UBVRI field photometry update
  75. The redshift of GRB 000418
  76. GRB 000429, optical observation
  77. GRB 000429, UBVRI field photometry
  78. IPN localization of GRB000429
  79. GRB 000418, UBVRI field photometry
  80. GRB000418, K'-band photometry
  81. GRB 000418, Optical Observation
  82. GRB 000418, optical observation
  83. GRB000424 Optical Observations
  84. GRB 000418, Optical Observation
  85. GRB 000424, Optical Observations
  86. GRB 000418, Optical Observation
  87. GRB000418, near-infrared observations
  88. Correction to IPN error box for GRB000419
  89. IPN error box for GRB000418
  90. GRB000419 [IPN Position]
  91. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  92. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  93. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  94. Budget cuts in BeppoSAX operations: impact on GRB observations
  95. GRB 000408, optical observations
  96. Refined IPN error box for GRB000408
  97. GRB 991208, UBVRI field photometry
  98. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  99. GRB000408 [IPN Position]
  100. GRB000326 Optical Observations

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