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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"

35270 results found.

  1. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  2. GRB000616 [IPN Position]
  3. GRB000615B [IPN Position]
  4. GRB000615, further R-band photometry
  5. GRB 000615: NIR observations
  6. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  7. GRB000615, R-band photometry
  8. GRB980425, HST/STIS observations of the host galaxy
  9. GRB000615: BeppoSAX GRB Alert
  10. The Hosts of GRB 980703 and GRB 971214
  11. GRB 000301C: Further Late-Time HST/STIS observations
  12. GRB000528: follow-up X-ray measurements and update of IPN annulus
  13. GRB980519, HST/STIS observations of the host galaxy
  14. GRB000607, Radio Observations
  15. GRB000604 - Optical observations
  16. GRB000607, A SHORT, HARD BURST
  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. GRB000604 [IPN Position]
  23. X-ray Afterglow of GRB 000529
  24. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  25. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  26. IPN localization and time history of GRB000528
  27. New IPN localization of GRB000529
  28. GRB 000528 - WFC measurements
  29. GRB000528: BeppoSAX GRBM observations
  30. GRB 000528 Optical Observations
  31. GRB000519, BVRI field photometry
  32. IPN triangulation of GRB000519
  33. IPN triangulation of GRB000516
  34. Re: GRB000508B : Optical observations
  35. GRB 000418, Optical observation
  36. GRB000508B, optical photometry
  37. GRB000508B, BVR field photometry
  38. Possible GRB-related phenomenon
  39. RXTE/ASM and IPN localization of GRB 000508B
  40. GRB000424, UBVRI field photometry
  41. GRB 000424 Optical Observations
  42. GRB000418, UBVRI field photometry update
  43. The redshift of GRB 000418
  44. GRB 000429, optical observation
  45. GRB 000429, UBVRI field photometry
  46. IPN localization of GRB000429
  47. GRB 000418, UBVRI field photometry
  48. GRB000418, K'-band photometry
  49. GRB 000418, Optical Observation
  50. GRB 000418, optical observation
  51. GRB000424 Optical Observations
  52. GRB 000418, Optical Observation
  53. GRB 000424, Optical Observations
  54. GRB 000418, Optical Observation
  55. GRB000418, near-infrared observations
  56. Correction to IPN error box for GRB000419
  57. IPN error box for GRB000418
  58. GRB000419 [IPN Position]
  59. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  60. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  61. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  62. Budget cuts in BeppoSAX operations: impact on GRB observations
  63. GRB 000408, optical observations
  64. Refined IPN error box for GRB000408
  65. GRB 991208, UBVRI field photometry
  66. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  67. GRB000408 [IPN Position]
  68. GRB000326 Optical Observations
  69. GRB000301C - Addendum to GCN 623
  70. GRB000301C - R magnitude lower limit
  71. GRB 000323, optical observations
  72. GRB 000326: Optical Observations
  73. GRB000326, Radio observations
  74. GRB000326 [IPN Position]
  75. GRB 000307 optical observations
  76. GRB000323 [IPN Position]
  77. GRB000315 [IPN Positions]
  78. GRB 000313 - optical transient in the BATSE error box
  79. GRB000301C - B and R photometry
  80. GRB000301C - R photometry
  81. GRB 000307, Optical Observations
  82. GRB 000307, BVRI Field Photometry
  83. GRB 000301C: Optical Spectrum and Redshift
  84. GRB 000301C: Optical Spectrum and Redshift
  85. GRB 000301C: A Precise Redshift Determination
  86. GRB 000301C, Optical Observation
  87. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  88. GRB 000301C: HST/STIS CCD Imaging of the field
  89. IPN error box for GRB000307
  90. GRB 000301c: K' observations
  91. GRB000301C, optical R-band observations
  92. GRB000301c - R photometry and nearby faint source confirmation
  93. GRB 000301C, Optical Observation
  94. GRB 000301c: K' observations
  95. GRB 000301C Optical Observations
  96. GRB 000301C: K' Observations
  97. GRB000301C - Host galaxy not detected in R (?)
  98. GRB000301C optical observations
  99. GRB 000301c near-IR observations
  100. GRB 000301C, Optical Color

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