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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"

39175 results found.

  1. GRB 000615: NIR observations
  2. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  3. GRB000615, R-band photometry
  4. GRB980425, HST/STIS observations of the host galaxy
  5. GRB000615: BeppoSAX GRB Alert
  6. The Hosts of GRB 980703 and GRB 971214
  7. GRB 000301C: Further Late-Time HST/STIS observations
  8. GRB000528: follow-up X-ray measurements and update of IPN annulus
  9. GRB980519, HST/STIS observations of the host galaxy
  10. GRB000607, Radio Observations
  11. GRB000604 - Optical observations
  12. GRB000607, A SHORT, HARD BURST
  13. GRB000604, optical observations
  14. GRB000528, optical observations at ESO
  15. GRB 000604 optical observations
  16. GRB 000418: Detection of the Host Galaxy
  17. GRB000604, optical observations, comparison with DPOSS
  18. GRB000604 [IPN Position]
  19. X-ray Afterglow of GRB 000529
  20. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  21. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  22. IPN localization and time history of GRB000528
  23. New IPN localization of GRB000529
  24. GRB 000528 - WFC measurements
  25. GRB000528: BeppoSAX GRBM observations
  26. GRB 000528 Optical Observations
  27. GRB000519, BVRI field photometry
  28. IPN triangulation of GRB000519
  29. IPN triangulation of GRB000516
  30. Re: GRB000508B : Optical observations
  31. GRB 000418, Optical observation
  32. GRB000508B, optical photometry
  33. GRB000508B, BVR field photometry
  34. Possible GRB-related phenomenon
  35. RXTE/ASM and IPN localization of GRB 000508B
  36. GRB000424, UBVRI field photometry
  37. GRB 000424 Optical Observations
  38. GRB000418, UBVRI field photometry update
  39. The redshift of GRB 000418
  40. GRB 000429, optical observation
  41. GRB 000429, UBVRI field photometry
  42. IPN localization of GRB000429
  43. GRB 000418, UBVRI field photometry
  44. GRB000418, K'-band photometry
  45. GRB 000418, Optical Observation
  46. GRB 000418, optical observation
  47. GRB000424 Optical Observations
  48. GRB 000418, Optical Observation
  49. GRB 000424, Optical Observations
  50. GRB 000418, Optical Observation
  51. GRB000418, near-infrared observations
  52. Correction to IPN error box for GRB000419
  53. IPN error box for GRB000418
  54. GRB000419 [IPN Position]
  55. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  56. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  57. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  58. Budget cuts in BeppoSAX operations: impact on GRB observations
  59. GRB 000408, optical observations
  60. Refined IPN error box for GRB000408
  61. GRB 991208, UBVRI field photometry
  62. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  63. GRB000408 [IPN Position]
  64. GRB000326 Optical Observations
  65. GRB000301C - Addendum to GCN 623
  66. GRB000301C - R magnitude lower limit
  67. GRB 000323, optical observations
  68. GRB 000326: Optical Observations
  69. GRB000326, Radio observations
  70. GRB000326 [IPN Position]
  71. GRB 000307 optical observations
  72. GRB000323 [IPN Position]
  73. GRB000315 [IPN Positions]
  74. GRB 000313 - optical transient in the BATSE error box
  75. GRB000301C - B and R photometry
  76. GRB000301C - R photometry
  77. GRB 000307, Optical Observations
  78. GRB 000307, BVRI Field Photometry
  79. GRB 000301C: Optical Spectrum and Redshift
  80. GRB 000301C: Optical Spectrum and Redshift
  81. GRB 000301C: A Precise Redshift Determination
  82. GRB 000301C, Optical Observation
  83. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  84. GRB 000301C: HST/STIS CCD Imaging of the field
  85. IPN error box for GRB000307
  86. GRB 000301c: K' observations
  87. GRB000301C, optical R-band observations
  88. GRB000301c - R photometry and nearby faint source confirmation
  89. GRB 000301C, Optical Observation
  90. GRB 000301c: K' observations
  91. GRB 000301C Optical Observations
  92. GRB 000301C: K' Observations
  93. GRB000301C - Host galaxy not detected in R (?)
  94. GRB000301C, Radio observations
  95. GRB000301C, Radio observations
  96. GRB000301C optical observations
  97. GRB 000301c near-IR observations
  98. GRB 000301C, Optical Color
  99. GRB000301C, Optical Spectroscopy
  100. GRB 000301C, UBVRI field photometry

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