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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"

24605 results found.

  1. GRB 990510: Possible detection of a host galaxy
  2. GRB 990510 Host Galaxy Discovery
  3. IPN localization of GRB000727
  4. GRB 990712: Late time HST/STIS Observations
  5. GRB 991216, HST/STIS observations
  6. GRB000620, Radio Observations
  7. GRB000630, optical observations
  8. GRB000630, Revised BVRI Field Photometry
  9. GRB000630, Optical Observations
  10. GRB000630, optical observations
  11. GRB000630, optical observations
  12. GRB000630, BVRI Field Photometry
  13. GRB000630, optical observations
  14. GRB000630: Optical observations
  15. GRB000630, Radio Observations
  16. possible optical counterpart of GRB 000630
  17. GRB 000620, optical observations
  18. GRB000418, HST/STIS Observations
  19. GRB990123: Late-time HST/STIS observations of the host
  20. GRB000620, optical observations
  21. GRB000615: H-band observations
  22. GRB990308, HST/STIS observations of the host galaxy
  23. GRB000620 - Optical observations
  24. GRB000620 Optical observations
  25. GRB000620: BeppoSAX WFC and GRBM detection
  26. GRB000607, optical observations
  27. GRB 000615: NIR further observations
  28. GRB990123, HST/STIS observations of the host galaxy
  29. GRB000616 optical observations
  30. GRB 000615, near-infrared observations
  31. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  32. GRB000615, further R-band photometry
  33. GRB 000615: NIR observations
  34. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  35. GRB000615, R-band photometry
  36. The Hosts of GRB 980703 and GRB 971214
  37. GRB 000301C: Further Late-Time HST/STIS observations
  38. GRB000528: follow-up X-ray measurements and update of IPN annulus
  39. GRB980519, HST/STIS observations of the host galaxy
  40. GRB000604 optical non-detection
  41. GRB000604 - Optical observations
  42. GRB000604, optical observations
  43. GRB000528, optical observations at ESO
  44. GRB 000604 optical observations
  45. GRB 000418: Detection of the Host Galaxy
  46. GRB000604, optical observations, comparison with DPOSS
  47. GRB000528, Radio Observations
  48. X-ray Afterglow of GRB 000529
  49. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  50. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  51. GRB 000528 - WFC measurements
  52. GRB000519, BVRI field photometry
  53. IPN triangulation of GRB000519
  54. GRB000508B, optical photometry
  55. GRB000508B, BVR field photometry
  56. Possible GRB-related phenomenon
  57. RXTE/ASM and IPN localization of GRB 000508B
  58. GRB000424, UBVRI field photometry
  59. GRB000418, UBVRI field photometry update
  60. GRB000424, optical observations
  61. GRB 000429, optical observation
  62. GRB 000429, UBVRI field photometry
  63. GRB 000418, UBVRI field photometry
  64. GRB 000418, optical observation
  65. GRB 000418, Optical Observation
  66. GRB000418, near-infrared observations
  67. Correction to IPN error box for GRB000419
  68. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  69. GRB000416 BRJK observations
  70. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  71. GRB 000408, optical observations
  72. GRB 991208, UBVRI field photometry
  73. GRB000408, lotis optical observations
  74. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  75. GRB000301C - Addendum to GCN 623
  76. GRB 000323, optical observations
  77. GRB 000326: Optical Observations
  78. GRB000326, Radio observations
  79. GRB000313, Radio observations
  80. GRB 000313 - optical transient in the BATSE error box
  81. GRB 000307, Optical Observations
  82. GRB 000307, BVRI Field Photometry
  83. GRB 000301C: A Precise Redshift Determination
  84. GRB 000301C, Optical Observation
  85. GRB 000301C: HST/STIS CCD Imaging of the field
  86. IPN error box for GRB000307
  87. GRB000301C, optical R-band observations
  88. GRB 000301C Optical Observations
  89. GRB 000301C: K' Observations
  90. GRB000301C OT candidate optical observations
  91. GRB000301C - Host galaxy not detected in R (?)
  92. Optical observations of GRB000301c
  93. GRB000301C, Radio observations
  94. GRB000301C, Radio observations
  95. GRB000301C, near-infrared observations (JHK' imaging)
  96. GRB 000301c near-IR observations
  97. GRB 000301C, UBVRI field photometry
  98. GRB 000301C: OT confirmed
  99. GRB000301c optical observations
  100. GRB000301C, optical observations

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