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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"

24598 results found.

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

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