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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"

24596 results found.

  1. GRB000630, optical observations
  2. GRB000630, optical observations
  3. GRB000630, BVRI Field Photometry
  4. GRB000630, optical observations
  5. GRB000630: Optical observations
  6. GRB000630, Radio Observations
  7. possible optical counterpart of GRB 000630
  8. GRB 000620, optical observations
  9. GRB000418, HST/STIS Observations
  10. GRB990123: Late-time HST/STIS observations of the host
  11. GRB000620, optical observations
  12. GRB000615: H-band observations
  13. GRB990308, HST/STIS observations of the host galaxy
  14. GRB000620 - Optical observations
  15. GRB000620 Optical observations
  16. GRB000620: BeppoSAX WFC and GRBM detection
  17. GRB000607, optical observations
  18. GRB 000615: NIR further observations
  19. GRB990123, HST/STIS observations of the host galaxy
  20. GRB000616 optical observations
  21. GRB 000615, near-infrared observations
  22. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  23. GRB000615, further R-band photometry
  24. GRB 000615: NIR observations
  25. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  26. GRB000615, R-band photometry
  27. The Hosts of GRB 980703 and GRB 971214
  28. GRB 000301C: Further Late-Time HST/STIS observations
  29. GRB000528: follow-up X-ray measurements and update of IPN annulus
  30. GRB980519, HST/STIS observations of the host galaxy
  31. GRB000604 optical non-detection
  32. GRB000604 - Optical observations
  33. GRB000604, optical observations
  34. GRB000528, optical observations at ESO
  35. GRB 000604 optical observations
  36. GRB 000418: Detection of the Host Galaxy
  37. GRB000604, optical observations, comparison with DPOSS
  38. GRB000528, Radio Observations
  39. X-ray Afterglow of GRB 000529
  40. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  41. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  42. GRB 000528 - WFC measurements
  43. GRB000519, BVRI field photometry
  44. IPN triangulation of GRB000519
  45. GRB000508B, optical photometry
  46. GRB000508B, BVR field photometry
  47. Possible GRB-related phenomenon
  48. RXTE/ASM and IPN localization of GRB 000508B
  49. GRB000424, UBVRI field photometry
  50. GRB000418, UBVRI field photometry update
  51. GRB000424, optical observations
  52. GRB 000429, optical observation
  53. GRB 000429, UBVRI field photometry
  54. GRB 000418, UBVRI field photometry
  55. GRB 000418, optical observation
  56. GRB 000418, Optical Observation
  57. GRB000418, near-infrared observations
  58. Correction to IPN error box for GRB000419
  59. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  60. GRB000416 BRJK observations
  61. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  62. GRB 000408, optical observations
  63. GRB 991208, UBVRI field photometry
  64. GRB000408, lotis optical observations
  65. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  66. GRB000301C - Addendum to GCN 623
  67. GRB 000323, optical observations
  68. GRB 000326: Optical Observations
  69. GRB000326, Radio observations
  70. GRB000313, Radio observations
  71. GRB 000313 - optical transient in the BATSE error box
  72. GRB 000307, Optical Observations
  73. GRB 000307, BVRI Field Photometry
  74. GRB 000301C: A Precise Redshift Determination
  75. GRB 000301C, Optical Observation
  76. GRB 000301C: HST/STIS CCD Imaging of the field
  77. IPN error box for GRB000307
  78. GRB000301C, optical R-band observations
  79. GRB 000301C Optical Observations
  80. GRB 000301C: K' Observations
  81. GRB000301C OT candidate optical observations
  82. GRB000301C - Host galaxy not detected in R (?)
  83. Optical observations of GRB000301c
  84. GRB000301C, Radio observations
  85. GRB000301C, Radio observations
  86. GRB000301C, near-infrared observations (JHK' imaging)
  87. GRB 000301c near-IR observations
  88. GRB 000301C, UBVRI field photometry
  89. GRB 000301C: OT confirmed
  90. GRB000301c optical observations
  91. GRB000301C, optical observations
  92. GRB000301C
  93. GRB 000301C : Optical Candidate
  94. GRB000301C: RXTE/ASM and IPN localizations
  95. GRB000226 [IPN Position]
  96. HST Observations of GRB 990712
  97. GRB 000214 near-IR observations
  98. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  99. GRB000210, Radio Observations
  100. GRB 000115, BVRI field photometry

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