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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').

19109 results found.

  1. IPN triangulation of GRB000519
  2. GRB000508B, optical photometry
  3. GRB000508B, BVR field photometry
  4. Possible GRB-related phenomenon
  5. RXTE/ASM and IPN localization of GRB 000508B
  6. GRB000424, UBVRI field photometry
  7. GRB000418, UBVRI field photometry update
  8. The redshift of GRB 000418
  9. GRB000424, optical observations
  10. GRB 000429, optical observation
  11. GRB 000429, UBVRI field photometry
  12. GRB 000418, UBVRI field photometry
  13. GRB 000418, optical observation
  14. GRB000424 Optical Observations
  15. GRB 000418, Optical Observation
  16. Correction to IPN error box for GRB000419
  17. IPN error box for GRB000418
  18. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  19. GRB 000408, optical observations
  20. GRB 991208, UBVRI field photometry
  21. GRB000408, lotis optical observations
  22. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  23. GRB000408 [IPN Position]
  24. GRB000301C - Addendum to GCN 623
  25. GRB 000326: Optical Observations
  26. GRB000326, Radio observations
  27. GRB000315 [IPN Positions]
  28. GRB000313, Radio observations
  29. GRB 000313 - optical transient in the BATSE error box
  30. GRB 000307, BVRI Field Photometry
  31. GRB 000301C: HST/STIS CCD Imaging of the field
  32. IPN error box for GRB000307
  33. GRB000301C, optical R-band observations
  34. GRB000301c - R photometry and nearby faint source confirmation
  35. GRB 000301C Optical Observations
  36. GRB 000301C: K' Observations
  37. GRB000301C - Host galaxy not detected in R (?)
  38. Optical observations of GRB000301c
  39. GRB000301C, Radio observations
  40. GRB000301C, Radio observations
  41. GRB 000301c near-IR observations
  42. GRB 000301C, UBVRI field photometry
  43. GRB000301C, near-infrared observations (JHK' photometry)
  44. GRB 000301C: OT confirmed
  45. GRB000301c optical observations
  46. GRB000301c, near-infrared observations
  47. GRB000301C
  48. GRB 000301C : Optical Candidate
  49. GRB000301C: RXTE/ASM and IPN localizations
  50. GRB000226 [IPN Position]
  51. HST Observations of GRB 990712
  52. GRB 000214 near-IR observations
  53. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  54. GRB000210, Radio Observations
  55. GRB 000115, BVRI field photometry
  56. GRB000214: BeppoSAX GRBM and WFC Detection
  57. Optical observations of GRB000210
  58. GRB000210 X-ray afterglow
  59. GRB000214: X-ray afterglow candidate
  60. GRB000214 refined BeppoSAX-WFC position
  61. GRB 000210: BATSE Observations
  62. Optical observations of the Chandra X-ray source for GRB000210
  63. GRB000210, Radio Observations
  64. GRB000201, Radio Observations
  65. GRB000210: BeppoSAX GRBM and WFC Detection
  66. Optical observations of GRB000131
  67. GRB000201 Optical Observations
  68. GRB 000201: TAROT optical observations
  69. IPN localization of GRB000131
  70. GRB 000126, optical observations
  71. IPN localization of GRB000126
  72. BATSE Observations of GRB000115
  73. GRB991216, UBVRIJHK field photometry
  74. GCN resumes full operations
  75. IPN error boxes for GRB991229
  76. GRB 991216: Detection of the Host and/or Absorber Galaxy
  77. IPN error boxes for GRB991221
  78. IPN error box for GRB991216
  79. GRB 991217 (SAX J2303.2+0015) Optical observations
  80. Chandra observation of the X-ray afterglow of GRB991216
  81. GRB 991216, optical observations
  82. GRB 991216 Optical spectroscopy/imaging
  83. GRB991216 Optical and IR observations
  84. SAX J2303.2+0015 Optical observations
  85. IR observations of GRB991216
  86. GRB 991217 (SAX J2303.2+0015) Optical observations
  87. GRB991216 Optical and infrared observations of Beethoven Burst
  88. GRB 991216 Radio Observations
  89. GRB 991208 Infrared Detection
  90. GRB991216
  91. GRB 991216--Summary of RXTE Observations
  92. GRB 991216 Optical Observations
  93. GRB 991216, optical observations
  94. GRB 991208 SAO-RAS Spectroscopy
  95. SAX J2303.2+0015: an x-ray/GRB?
  96. GRB 991216, Optical Transient
  97. GRB991216 ('Beethoven Burst') B, R, and K Observations
  98. GRB991216, infrared observations
  99. GRB 991208 optical observations
  100. Lowell/Perkins observation of GRB 991216

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