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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"

25980 results found.

  1. GRB000607, optical observations
  2. GRB 000615: NIR further observations
  3. GRB990123, HST/STIS observations of the host galaxy
  4. GRB000616 optical observations
  5. GRB 000615, near-infrared observations
  6. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  7. GRB000615, further R-band photometry
  8. GRB 000615: NIR observations
  9. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  10. GRB000615, R-band photometry
  11. The Hosts of GRB 980703 and GRB 971214
  12. GRB 000301C: Further Late-Time HST/STIS observations
  13. GRB000528: follow-up X-ray measurements and update of IPN annulus
  14. GRB980519, HST/STIS observations of the host galaxy
  15. GRB000604 optical non-detection
  16. GRB000604 - Optical observations
  17. GRB000604, optical observations
  18. GRB000528, optical observations at ESO
  19. GRB 000604 optical observations
  20. GRB 000418: Detection of the Host Galaxy
  21. GRB000604, optical observations, comparison with DPOSS
  22. GRB000528, Radio Observations
  23. X-ray Afterglow of GRB 000529
  24. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  25. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  26. GRB 000528 - WFC measurements
  27. GRB000519, BVRI field photometry
  28. IPN triangulation of GRB000519
  29. GRB000508B, optical photometry
  30. GRB000508B, BVR field photometry
  31. Possible GRB-related phenomenon
  32. RXTE/ASM and IPN localization of GRB 000508B
  33. GRB000424, UBVRI field photometry
  34. GRB000418, UBVRI field photometry update
  35. GRB000424, optical observations
  36. GRB 000429, optical observation
  37. GRB 000429, UBVRI field photometry
  38. GRB 000418, UBVRI field photometry
  39. GRB 000418, optical observation
  40. GRB 000418, Optical Observation
  41. GRB000418, near-infrared observations
  42. Correction to IPN error box for GRB000419
  43. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  44. GRB000416 BRJK observations
  45. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  46. GRB 000408, optical observations
  47. GRB 991208, UBVRI field photometry
  48. GRB000408, lotis optical observations
  49. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  50. GRB000301C - Addendum to GCN 623
  51. GRB 000323, optical observations
  52. GRB 000326: Optical Observations
  53. GRB000326, Radio observations
  54. GRB000313, Radio observations
  55. GRB 000313 - optical transient in the BATSE error box
  56. GRB 000307, Optical Observations
  57. GRB 000307, BVRI Field Photometry
  58. GRB 000301C: A Precise Redshift Determination
  59. GRB 000301C, Optical Observation
  60. GRB 000301C: HST/STIS CCD Imaging of the field
  61. IPN error box for GRB000307
  62. GRB000301C, optical R-band observations
  63. GRB 000301C Optical Observations
  64. GRB 000301C: K' Observations
  65. GRB000301C OT candidate optical observations
  66. GRB000301C - Host galaxy not detected in R (?)
  67. Optical observations of GRB000301c
  68. GRB000301C, Radio observations
  69. GRB000301C, Radio observations
  70. GRB000301C, near-infrared observations (JHK' imaging)
  71. GRB 000301c near-IR observations
  72. GRB 000301C, UBVRI field photometry
  73. GRB 000301C: OT confirmed
  74. GRB000301c optical observations
  75. GRB000301C, optical observations
  76. GRB000301C
  77. GRB 000301C : Optical Candidate
  78. GRB000301C: RXTE/ASM and IPN localizations
  79. GRB000226 [IPN Position]
  80. HST Observations of GRB 990712
  81. GRB 000214 near-IR observations
  82. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  83. GRB000210, Radio Observations
  84. GRB 000115, BVRI field photometry
  85. GRB000214: BeppoSAX GRBM and WFC Detection
  86. Optical observations of GRB000210
  87. GRB000210 X-ray afterglow
  88. GRB000214: X-ray afterglow candidate
  89. GRB000214 refined BeppoSAX-WFC position
  90. GRB 000210: BATSE Observations
  91. Optical observations of the Chandra X-ray source for GRB000210
  92. GRB000210, Radio Observations
  93. IPN triangulation of GRB000210
  94. GRB000210: possible afterglow detection with BeppoSAX NFI
  95. GRB000201, Radio Observations
  96. GRB000210: BeppoSAX GRBM and WFC Detection
  97. SAX_WFC_GRB_NOTICE
  98. SAX_WFC_GRB_NOTICE
  99. GRB000201 Optical Observations
  100. GRB 000201: TAROT optical observations

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