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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"

21767 results found.

  1. GRB000801, VLT-Antu R-band observations
  2. GRB 991208 Host Galaxy Imaging
  3. IPN localization of GRB000801
  4. IPN localization of GRB000730B
  5. GRB 990510: Possible detection of a host galaxy
  6. GRB 990510 Host Galaxy Discovery
  7. GRB 990705, HST/STIS observations of the host galaxy
  8. GRB 990712: Late time HST/STIS Observations
  9. GRB 991216, HST/STIS observations
  10. GRB000630, optical observations
  11. GRB000630, Revised BVRI Field Photometry
  12. GRB000630, Optical Observations
  13. GRB000630, optical observations
  14. GRB000630, optical observations
  15. GRB000630, BVRI Field Photometry
  16. GRB000630, optical observations
  17. GRB000630: Optical observations
  18. possible optical counterpart of GRB 000630
  19. IPN triangulation of GRB000630
  20. GRB 000620, optical observations
  21. GRB000418, HST/STIS Observations
  22. GRB990123: Late-time HST/STIS observations of the host
  23. GRB000623
  24. GRB000620, optical observations
  25. GRB000615: H-band observations
  26. GRB000620 - Optical observations
  27. GRB000620 Optical observations
  28. GRB000620: BeppoSAX WFC and GRBM detection
  29. GRB000615, Radio observations
  30. GRB000607, optical observations
  31. GRB 000615: NIR further observations
  32. BeppoSAX ALERT: GRB000620
  33. GRB000620: BeppoSAX Alert
  34. GRB000616 optical observations
  35. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  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. GRB000615: BeppoSAX GRB Alert
  41. The Hosts of GRB 980703 and GRB 971214
  42. GRB 000301C: Further Late-Time HST/STIS observations
  43. GRB000528: follow-up X-ray measurements and update of IPN annulus
  44. GRB000607, Radio Observations
  45. GRB000604 - Optical observations
  46. GRB000604, optical observations
  47. GRB000528, optical observations at ESO
  48. GRB 000418: Detection of the Host Galaxy
  49. GRB000604, optical observations, comparison with DPOSS
  50. GRB000604 [IPN Position]
  51. GRB000528, Radio Observations
  52. X-ray Afterglow of GRB 000529
  53. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  54. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  55. GRB000519: Optical observations
  56. GRB 000528 - WFC measurements
  57. GRB000528: BeppoSAX GRBM observations
  58. GRB000519, BVRI field photometry
  59. IPN triangulation of GRB000519
  60. GRB000508B, optical photometry
  61. GRB000508B, BVR field photometry
  62. Possible GRB-related phenomenon
  63. RXTE/ASM and IPN localization of GRB 000508B
  64. GRB000424, UBVRI field photometry
  65. GRB000418, UBVRI field photometry update
  66. The redshift of GRB 000418
  67. GRB000424, optical observations
  68. GRB 000429, optical observation
  69. GRB 000429, UBVRI field photometry
  70. GRB 000418, UBVRI field photometry
  71. GRB 000418, optical observation
  72. GRB000424 Optical Observations
  73. GRB 000418, Optical Observation
  74. Correction to IPN error box for GRB000419
  75. IPN error box for GRB000418
  76. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  77. GRB 000408, optical observations
  78. GRB 991208, UBVRI field photometry
  79. GRB000408, lotis optical observations
  80. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  81. GRB000408 [IPN Position]
  82. GRB000301C - Addendum to GCN 623
  83. GRB 000326: Optical Observations
  84. GRB000326, Radio observations
  85. GRB000315 [IPN Positions]
  86. GRB000313, Radio observations
  87. GRB 000313 - optical transient in the BATSE error box
  88. GRB 000307, BVRI Field Photometry
  89. GRB 000301C: HST/STIS CCD Imaging of the field
  90. IPN error box for GRB000307
  91. GRB000301C, optical R-band observations
  92. GRB000301c - R photometry and nearby faint source confirmation
  93. GRB 000301C Optical Observations
  94. GRB 000301C: K' Observations
  95. GRB000301C - Host galaxy not detected in R (?)
  96. Optical observations of GRB000301c
  97. GRB000301C, Radio observations
  98. GRB000301C, Radio observations
  99. GRB 000301c near-IR observations
  100. GRB 000301C, UBVRI field photometry

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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