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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').

24549 results found.

  1. RXTE/ASM and IPN localization of GRB 000508B
  2. GRB000424, UBVRI field photometry
  3. GRB000418, UBVRI field photometry update
  4. GRB000424, optical observations
  5. GRB 000429, optical observation
  6. GRB 000429, UBVRI field photometry
  7. GRB 000418, UBVRI field photometry
  8. GRB 000418, optical observation
  9. GRB 000418, Optical Observation
  10. GRB000418, near-infrared observations
  11. Correction to IPN error box for GRB000419
  12. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  13. GRB000416 BRJK observations
  14. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  15. GRB 000408, optical observations
  16. GRB 991208, UBVRI field photometry
  17. GRB000408, lotis optical observations
  18. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  19. GRB000301C - Addendum to GCN 623
  20. GRB 000323, optical observations
  21. GRB 000326: Optical Observations
  22. GRB000326, Radio observations
  23. GRB000313, Radio observations
  24. GRB 000313 - optical transient in the BATSE error box
  25. GRB 000307, Optical Observations
  26. GRB 000307, BVRI Field Photometry
  27. GRB 000301C: A Precise Redshift Determination
  28. GRB 000301C, Optical Observation
  29. GRB 000301C: HST/STIS CCD Imaging of the field
  30. IPN error box for GRB000307
  31. GRB000301C, optical R-band observations
  32. GRB 000301C Optical Observations
  33. GRB 000301C: K' Observations
  34. GRB000301C OT candidate optical observations
  35. GRB000301C - Host galaxy not detected in R (?)
  36. Optical observations of GRB000301c
  37. GRB000301C, Radio observations
  38. GRB000301C, Radio observations
  39. GRB000301C, near-infrared observations (JHK' imaging)
  40. GRB 000301c near-IR observations
  41. GRB 000301C, UBVRI field photometry
  42. GRB 000301C: OT confirmed
  43. GRB000301c optical observations
  44. GRB000301C, optical observations
  45. GRB000301C
  46. GRB 000301C : Optical Candidate
  47. GRB000301C: RXTE/ASM and IPN localizations
  48. GRB000226 [IPN Position]
  49. HST Observations of GRB 990712
  50. GRB 000214 near-IR observations
  51. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  52. GRB000210, Radio Observations
  53. GRB 000115, BVRI field photometry
  54. GRB000214: BeppoSAX GRBM and WFC Detection
  55. Optical observations of GRB000210
  56. GRB000210 X-ray afterglow
  57. GRB000214: X-ray afterglow candidate
  58. GRB000214 refined BeppoSAX-WFC position
  59. GRB 000210: BATSE Observations
  60. Optical observations of the Chandra X-ray source for GRB000210
  61. GRB000210, Radio Observations
  62. IPN triangulation of GRB000210
  63. GRB000210: possible afterglow detection with BeppoSAX NFI
  64. GRB000201, Radio Observations
  65. GRB000210: BeppoSAX GRBM and WFC Detection
  66. SAX_WFC_GRB_NOTICE
  67. SAX_WFC_GRB_NOTICE
  68. GRB000201 Optical Observations
  69. GRB 000201: TAROT optical observations
  70. GRB 991208, radio observations
  71. BATSE+IPN location of GRB000131
  72. IPN localization of GRB000131
  73. GRB 000126, optical observations
  74. BATSE Observations of GRB000115
  75. Second RXTE Observation of GRB 000115
  76. GRB991216, UBVRIJHK field photometry
  77. GCN resumes full operations
  78. GRB 991216 VLBA Observations
  79. GRB 991216: J band spectrophotometry
  80. GRB 991216: Detection of the Host and/or Absorber Galaxy
  81. IPN localization of GRB991226
  82. GRB 991216 RXTE ASM Observations
  83. GRB 991216: Updated BATSE parameters
  84. GRB 991217 (SAX J2303.2+0015) Optical observations
  85. Chandra observation of the X-ray afterglow of GRB991216
  86. GRB 991216, optical observations
  87. GRB 991216 Optical spectroscopy/imaging
  88. SAX J2303.2+0015 Optical observations
  89. IR observations of GRB991216
  90. GRB 991217 (SAX J2303.2+0015) Optical observations
  91. GRB991216 Optical and infrared observations of Beethoven Burst
  92. GRB 991216 Radio Observations
  93. GRB 991208 Keck Spectroscopy
  94. GRB 991208 Infrared Detection
  95. GRB991216
  96. GRB 991216--Summary of RXTE Observations
  97. GRB 991216 Optical Observations
  98. GRB 991216, optical observations
  99. GRB 991208 SAO-RAS Spectroscopy
  100. SAX J2303.2+0015: an x-ray/GRB?

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