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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"

26001 results found.

  1. GRB 991216, HST/STIS observations
  2. GRB000620, Radio Observations
  3. GRB000630, optical observations
  4. GRB000630, Revised BVRI Field Photometry
  5. GRB000630, Optical Observations
  6. GRB000630, optical observations
  7. GRB000630, optical observations
  8. GRB000630, BVRI Field Photometry
  9. GRB000630, optical observations
  10. GRB000630: Optical observations
  11. GRB000630, Radio Observations
  12. possible optical counterpart of GRB 000630
  13. GRB 000620, optical observations
  14. GRB000418, HST/STIS Observations
  15. GRB990123: Late-time HST/STIS observations of the host
  16. GRB000620, optical observations
  17. GRB000615: H-band observations
  18. GRB990308, HST/STIS observations of the host galaxy
  19. GRB000620 - Optical observations
  20. GRB000620 Optical observations
  21. GRB000620: BeppoSAX WFC and GRBM detection
  22. GRB000607, optical observations
  23. GRB 000615: NIR further observations
  24. GRB990123, HST/STIS observations of the host galaxy
  25. GRB000616 optical observations
  26. GRB 000615, near-infrared observations
  27. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  28. GRB000615, further R-band photometry
  29. GRB 000615: NIR observations
  30. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  31. GRB000615, R-band photometry
  32. The Hosts of GRB 980703 and GRB 971214
  33. GRB 000301C: Further Late-Time HST/STIS observations
  34. GRB000528: follow-up X-ray measurements and update of IPN annulus
  35. GRB980519, HST/STIS observations of the host galaxy
  36. GRB000604 optical non-detection
  37. GRB000604 - Optical observations
  38. GRB000604, optical observations
  39. GRB000528, optical observations at ESO
  40. GRB 000604 optical observations
  41. GRB 000418: Detection of the Host Galaxy
  42. GRB000604, optical observations, comparison with DPOSS
  43. GRB000528, Radio Observations
  44. X-ray Afterglow of GRB 000529
  45. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  46. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  47. GRB 000528 - WFC measurements
  48. GRB000519, BVRI field photometry
  49. IPN triangulation of GRB000519
  50. GRB000508B, optical photometry
  51. GRB000508B, BVR field photometry
  52. Possible GRB-related phenomenon
  53. RXTE/ASM and IPN localization of GRB 000508B
  54. GRB000424, UBVRI field photometry
  55. GRB000418, UBVRI field photometry update
  56. GRB000424, optical observations
  57. GRB 000429, optical observation
  58. GRB 000429, UBVRI field photometry
  59. GRB 000418, UBVRI field photometry
  60. GRB 000418, optical observation
  61. GRB 000418, Optical Observation
  62. GRB000418, near-infrared observations
  63. Correction to IPN error box for GRB000419
  64. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  65. GRB000416 BRJK observations
  66. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  67. GRB 000408, optical observations
  68. GRB 991208, UBVRI field photometry
  69. GRB000408, lotis optical observations
  70. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  71. GRB000301C - Addendum to GCN 623
  72. GRB 000323, optical observations
  73. GRB 000326: Optical Observations
  74. GRB000326, Radio observations
  75. GRB000313, Radio observations
  76. GRB 000313 - optical transient in the BATSE error box
  77. GRB 000307, Optical Observations
  78. GRB 000307, BVRI Field Photometry
  79. GRB 000301C: A Precise Redshift Determination
  80. GRB 000301C, Optical Observation
  81. GRB 000301C: HST/STIS CCD Imaging of the field
  82. IPN error box for GRB000307
  83. GRB000301C, optical R-band observations
  84. GRB 000301C Optical Observations
  85. GRB 000301C: K' Observations
  86. GRB000301C OT candidate optical observations
  87. GRB000301C - Host galaxy not detected in R (?)
  88. Optical observations of GRB000301c
  89. GRB000301C, Radio observations
  90. GRB000301C, Radio observations
  91. GRB000301C, near-infrared observations (JHK' imaging)
  92. GRB 000301c near-IR observations
  93. GRB 000301C, UBVRI field photometry
  94. GRB 000301C: OT confirmed
  95. GRB000301c optical observations
  96. GRB000301C, optical observations
  97. GRB000301C
  98. GRB 000301C : Optical Candidate
  99. GRB000301C: RXTE/ASM and IPN localizations
  100. GRB000226 [IPN Position]

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