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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').

22285 results found.

  1. GRB010213, Near-IR observations
  2. Possible InfraRed Transient of GRB 010214.
  3. GRB 010214, optical observations
  4. GRB010213 detected by HETE
  5. IPN Status Report
  6. HETE Status
  7. IPN/RXTE TRIANGULATION OF GRB010126
  8. GRB010126 Optical Observations
  9. IPN TRIANGULATION OF GRB010126
  10. Optical Observations of GRB 001018 at Keck
  11. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  12. Optical observations of GRB 001018 with JCAM
  13. IPN TRIANGULATION OF GRB010115
  14. IPN TRIANGULATION OF GRB010109
  15. IPN TRIANGULATION OF GRB010109
  16. IPN triangulation of GRB010104
  17. IPN triangulation of GRB010103
  18. H band observation of GRB 001212
  19. IPN triangulation of GRB001219
  20. GRB 001212 Optical Observation
  21. GRB 001212 Optical Observation
  22. GRB 001212 possible OA in 2MASS
  23. IPN triangulation of GRB001212
  24. Confirmation of IPN position for GRB001204
  25. IPN triangulation of GRB001204 (short/hard)
  26. GRB001120, optical observations
  27. WSRT 4.8 GHz observations of GRB001109
  28. IPN triangulation of GRB001120
  29. GRB 001109: deep JHK upper limits
  30. GRB 001109 X-ray afterglow with BeppoSAX
  31. CORRECTION to XMM-Newton observation of GRB001025
  32. GRB001109, Radio observations
  33. GRB001105 BVRI field photometry correction
  34. GRB001105, BVRI field photometry
  35. IPN TRIANGULATION OF GRB001105
  36. GRB 001025B, Optical obervations
  37. GRB 991208: HST Imaging of the Host Galaxy
  38. GRB 001025B, I-band observations
  39. XMM-Newton observation of GRB001025
  40. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  41. CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025
  42. GRB001007: Optical observations
  43. ASM Localization of GRB 001025
  44. GRB001007, Radio observations
  45. GRB 001018, Possible Radio Afterglow
  46. GRB001018, Gamma Ray Observations
  47. IPN TRIANGULATION OF GRB001019
  48. IPN TRIANGULATION OF GRB001018
  49. IPN TRIANGULATION OF GRB 001017
  50. V,R,I band observations of GRB000926
  51. HETE positions added to GCN
  52. GRB000926 - Amateur Optical Observations
  53. CONCAM null result on GRB001005
  54. IPN triangulation of GRB001005
  55. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  56. GRB000926 - Optical observations
  57. GRB000926 - Optical observations
  58. GRB 000926, Optical Decay
  59. GRB000911: VLT infrared observation
  60. GRB 000926, Optical Observations
  61. GRB000926 K'-band Observation
  62. J and K band observations of GRB 000926
  63. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  64. CONCAM crude optical limits before and after GRB000926
  65. GRB 000926: Preliminary R-band Lightcurve
  66. Spectroscopic Redshift of GRB 000926
  67. GRB 000926: Optical candidate
  68. Optical candidate for GRB000926
  69. GRB 000911, BVRI field photometry
  70. GRB000911, Radio and Optical observations
  71. GRB000911: Optical observations
  72. GRB000830, BVRI field photometry
  73. GRB000210, Optical observations
  74. "Snapshot" afterglow IDs and GRB 000830
  75. GRB000730, Gamma Ray Observations
  76. GRB000812, Radio observations
  77. GRB000801, Gamma Ray Observations
  78. GRB000801, VLT-Antu R-band observations
  79. GRB 991208 Host Galaxy Imaging
  80. IPN localization of GRB000730B
  81. GRB 990510: Possible detection of a host galaxy
  82. GRB 990510 Host Galaxy Discovery
  83. IPN localization of GRB000727
  84. GRB 990712: Late time HST/STIS Observations
  85. GRB 991216, HST/STIS observations
  86. GRB000620, Radio Observations
  87. GRB000630, optical observations
  88. GRB000630, Revised BVRI Field Photometry
  89. GRB000630, Optical Observations
  90. GRB000630, optical observations
  91. GRB000630, optical observations
  92. GRB000630, BVRI Field Photometry
  93. GRB000630, optical observations
  94. GRB000630: Optical observations
  95. GRB000630, Radio Observations
  96. possible optical counterpart of GRB 000630
  97. GRB 000620, optical observations
  98. GRB000418, HST/STIS Observations
  99. GRB990123: Late-time HST/STIS observations of the host
  100. GRB000620, optical observations

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