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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"

25984 results found.

  1. GRB990308, HST/STIS observations of the host galaxy
  2. GRB000620 - Optical observations
  3. GRB000620 Optical observations
  4. GRB000620: BeppoSAX WFC and GRBM detection
  5. GRB000607, optical observations
  6. GRB 000615: NIR further observations
  7. GRB990123, HST/STIS observations of the host galaxy
  8. GRB000616 optical observations
  9. GRB 000615, near-infrared observations
  10. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  11. GRB000615, further R-band photometry
  12. GRB 000615: NIR observations
  13. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  14. GRB000615, R-band photometry
  15. The Hosts of GRB 980703 and GRB 971214
  16. GRB 000301C: Further Late-Time HST/STIS observations
  17. GRB000528: follow-up X-ray measurements and update of IPN annulus
  18. GRB980519, HST/STIS observations of the host galaxy
  19. GRB000604 optical non-detection
  20. GRB000604 - Optical observations
  21. GRB000604, optical observations
  22. GRB000528, optical observations at ESO
  23. GRB 000604 optical observations
  24. GRB 000418: Detection of the Host Galaxy
  25. GRB000604, optical observations, comparison with DPOSS
  26. GRB000528, Radio Observations
  27. X-ray Afterglow of GRB 000529
  28. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  29. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  30. GRB 000528 - WFC measurements
  31. GRB000519, BVRI field photometry
  32. IPN triangulation of GRB000519
  33. GRB000508B, optical photometry
  34. GRB000508B, BVR field photometry
  35. Possible GRB-related phenomenon
  36. RXTE/ASM and IPN localization of GRB 000508B
  37. GRB000424, UBVRI field photometry
  38. GRB000418, UBVRI field photometry update
  39. GRB000424, optical observations
  40. GRB 000429, optical observation
  41. GRB 000429, UBVRI field photometry
  42. GRB 000418, UBVRI field photometry
  43. GRB 000418, optical observation
  44. GRB 000418, Optical Observation
  45. GRB000418, near-infrared observations
  46. Correction to IPN error box for GRB000419
  47. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  48. GRB000416 BRJK observations
  49. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  50. GRB 000408, optical observations
  51. GRB 991208, UBVRI field photometry
  52. GRB000408, lotis optical observations
  53. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  54. GRB000301C - Addendum to GCN 623
  55. GRB 000323, optical observations
  56. GRB 000326: Optical Observations
  57. GRB000326, Radio observations
  58. GRB000313, Radio observations
  59. GRB 000313 - optical transient in the BATSE error box
  60. GRB 000307, Optical Observations
  61. GRB 000307, BVRI Field Photometry
  62. GRB 000301C: A Precise Redshift Determination
  63. GRB 000301C, Optical Observation
  64. GRB 000301C: HST/STIS CCD Imaging of the field
  65. IPN error box for GRB000307
  66. GRB000301C, optical R-band observations
  67. GRB 000301C Optical Observations
  68. GRB 000301C: K' Observations
  69. GRB000301C OT candidate optical observations
  70. GRB000301C - Host galaxy not detected in R (?)
  71. Optical observations of GRB000301c
  72. GRB000301C, Radio observations
  73. GRB000301C, Radio observations
  74. GRB000301C, near-infrared observations (JHK' imaging)
  75. GRB 000301c near-IR observations
  76. GRB 000301C, UBVRI field photometry
  77. GRB 000301C: OT confirmed
  78. GRB000301c optical observations
  79. GRB000301C, optical observations
  80. GRB000301C
  81. GRB 000301C : Optical Candidate
  82. GRB000301C: RXTE/ASM and IPN localizations
  83. GRB000226 [IPN Position]
  84. HST Observations of GRB 990712
  85. GRB 000214 near-IR observations
  86. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  87. GRB000210, Radio Observations
  88. GRB 000115, BVRI field photometry
  89. GRB000214: BeppoSAX GRBM and WFC Detection
  90. Optical observations of GRB000210
  91. GRB000210 X-ray afterglow
  92. GRB000214: X-ray afterglow candidate
  93. GRB000214 refined BeppoSAX-WFC position
  94. GRB 000210: BATSE Observations
  95. Optical observations of the Chandra X-ray source for GRB000210
  96. GRB000210, Radio Observations
  97. IPN triangulation of GRB000210
  98. GRB000210: possible afterglow detection with BeppoSAX NFI
  99. GRB000201, Radio Observations
  100. GRB000210: BeppoSAX GRBM and WFC Detection

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