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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').

31197 results found.

  1. GRB000323 [IPN Position]
  2. GRB000315 [IPN Positions]
  3. GRB 000313 - optical transient in the BATSE error box
  4. GRB000301C - B and R photometry
  5. GRB000301C - R photometry
  6. GRB 000307, Optical Observations
  7. GRB 000307, BVRI Field Photometry
  8. GRB 000301C: Optical Spectrum and Redshift
  9. GRB 000301C: Optical Spectrum and Redshift
  10. GRB 000301C: A Precise Redshift Determination
  11. GRB 000301C, Optical Observation
  12. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  13. GRB 000301C: HST/STIS CCD Imaging of the field
  14. IPN error box for GRB000307
  15. GRB 000301c: K' observations
  16. GRB000301C, optical R-band observations
  17. GRB000301c - R photometry and nearby faint source confirmation
  18. GRB 000301C, Optical Observation
  19. GRB 000301c: K' observations
  20. GRB 000301C Optical Observations
  21. GRB 000301C: K' Observations
  22. GRB000301C - Host galaxy not detected in R (?)
  23. GRB000301C optical observations
  24. GRB 000301c near-IR observations
  25. GRB 000301C, Optical Color
  26. GRB000301C, Optical Spectroscopy
  27. GRB 000301C, UBVRI field photometry
  28. GRB 000301C, Optical Observation
  29. GRB000301C 250 GHz detection
  30. GRB 000301C R-band observation
  31. GRB 000301C, Optical Observation
  32. GRB000301C, near-infrared observations (JHK' photometry)
  33. GRB 000301C: OT confirmed
  34. GRB000301c optical observations
  35. GRB 000301A, Radio Observations
  36. GRB000301C, optical observations
  37. GRB000301c, near-infrared observations
  38. GRB000301C
  39. GRB 000301C : Optical Candidate
  40. GRB000301C: RXTE/ASM and IPN localizations
  41. GRB000226 [IPN Position]
  42. HST Observations of GRB 990712
  43. GRB 000214 near-IR observations
  44. GRB 000115 Optical observations
  45. GRB 000214, Radio Observations
  46. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  47. GRB 000115, BVRI field photometry
  48. IPN annulus for GRB000214
  49. BATSE GRB trigger criterion changed
  50. GRB000210 X-ray afterglow
  51. GRB000214: X-ray afterglow candidate
  52. BeppoSAX GRB000214 ("S. Valentine's day GRB")
  53. GRB 000210: BATSE Observations
  54. Optical observations of the Chandra X-ray source for GRB000210
  55. Chandra Observations of GRB000210 X-ray Afterglow
  56. IPN triangulation of GRB000210
  57. GRB 000201: TAROT optical observations
  58. GRB 000131 Optical Observations
  59. GRB000126 Optical Observations
  60. BATSE GRB trigger criteria changed
  61. GRB 991208, radio observations
  62. BATSE+IPN location of GRB000131
  63. IPN localization of GRB000131
  64. GRB 000126, optical observations
  65. GRB000126, optical observations
  66. BATSE location of GRB000126
  67. IPN localization of GRB000126
  68. GRB 000115 Optical observations
  69. BATSE Observations of GRB000115
  70. Second RXTE Observation of GRB 000115
  71. GRB991216, UBVRIJHK field photometry
  72. Single IPN error box for GRB991229
  73. GRB 991216 VLBA Observations
  74. BEPPOSAX GRBM Localization of GRB991226
  75. IPN error boxes for GRB991229
  76. GRB 991216: J band spectrophotometry
  77. GRB 991216: Detection of the Host and/or Absorber Galaxy
  78. IPN localization of GRB991226
  79. Single IPN error box for GRB991221
  80. IPN error boxes for GRB991221
  81. GRB 991216 RXTE ASM Observations
  82. IPN error box for GRB991216
  83. GRB 991216: Updated BATSE parameters
  84. Lowell/Perkins observation of GRB 991216
  85. GRB 991217 (SAX J2303.2+0015) Optical observations
  86. Chandra observation of the X-ray afterglow of GRB991216
  87. GRB 991216, optical observations
  88. GRB 991216 Optical Observations
  89. GRB 991216 Optical spectroscopy/imaging
  90. VLT spectra of GRB991216
  91. K observations of GRB991216
  92. GRB 991217 (SAX J2303.2+0015) Optical observations
  93. GRB991216 Spectroscopy
  94. Lowell/Perkins observation of GRB 991216
  95. GRB991216, optical observations
  96. Refined IPN localization of GRB991216
  97. GRB 991216 Radio Observations
  98. GRB 991217
  99. GRB 991208 Keck Spectroscopy
  100. GRB 991208 Infrared Detection

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