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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').

10041 results found.

  1. Optical Observations of GRB 010324
  2. GRB 010222 - HEGRA GeV/TeV Observations
  3. GRB010222, possible increase of optical decay slope
  4. GRB 010220: Near-IR Observations
  5. GRB 010222: Near-IR Observations
  6. GRB010214, candidate optical afterglow
  7. GRB010214, optical observations
  8. J-Band Observation of GRB 010214.
  9. Possible InfraRed Transient of GRB 010214.
  10. GRB010214 Optical Observation
  11. GRB010213 detected by HETE
  12. GRB010126, TNG R-band observations
  13. Optical Observations of GRB 001018 at Keck
  14. H band observation of GRB 001212
  15. GRB 001109: deep JHK upper limits
  16. CORRECTION to XMM-Newton observation of GRB001025
  17. XMM-Newton observation of GRB001025
  18. V,R,I band observations of GRB000926
  19. The Likely Optical/Infrared Afterglow of GRB 001011
  20. Public availability of BeppoSAX data of GRB000926
  21. GRB000926: X-ray afterglow by BeppoSAX: revised fluxes (fwd)
  22. GRB 000926, Optical Decay
  23. GRB 000926, Optical Observations
  24. J and K band observations of GRB 000926
  25. GRB 000926, Optical Observation
  26. Optical candidate for GRB000926
  27. GRB000830, TNG B-band observations
  28. GRB000210, Optical observations
  29. Chandra Position of GRB000210
  30. GRB000812, TNG R-band observations
  31. GRB000801, VLT-Antu R-band observations
  32. GRB000630, optical observations
  33. GRB000418, HST/STIS Observations
  34. GRB000620, optical observations
  35. GRB000615: H-band observations
  36. GRB000620 Optical observations
  37. GRB000607, optical observations
  38. GRB000616 optical observations
  39. GRB 000615: NIR observations
  40. Optical Follow-up of GRB000529 Error Box
  41. GRB000528, optical observations at ESO
  42. Re: GRB000508B : Optical observations
  43. GRB 000424 Optical Observations
  44. GRB 000418, Optical Observation
  45. GRB000424 Optical Observations
  46. GRB 000418, Optical Observation
  47. GRB 000418, Optical Observation
  48. BeppoSAX GRB000424
  49. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  50. GRB 000301C: Optical Spectrum and Redshift
  51. GRB 000301C: Optical Spectrum and Redshift
  52. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  53. GRB000301C, optical R-band observations
  54. GRB 000301C: K' Observations
  55. GRB000301C - Host galaxy not detected in R (?)
  56. GRB 000301c near-IR observations
  57. GRB 000301C, Optical Color
  58. GRB 000301C, Optical Observation
  59. GRB 000301C, Optical Observation
  60. GRB 000115 Optical observations
  61. GRB 000115 Optical observations
  62. GRB 991216: J band spectrophotometry
  63. GRB991217/SAX J2303.2+0015, optical observations
  64. Chandra observation of the X-ray afterglow of GRB991216
  65. GRB 991208 Keck Spectroscopy
  66. GRB 991208 Infrared Detection
  67. GRB 991216: Comparison with DPOSS images
  68. R-band Observations of GRB991208 at TNG
  69. GRB991208, optical observations
  70. Optical Observations of GRB991105
  71. GRB991106, optical observation at SAO-RAS
  72. Revised BeppoSAX WFC position of GRB991105
  73. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
  74. GRB 991014, radio observations
  75. GRB 991014, Optical Observations
  76. Optical Observations of GRB990907
  77. BeppoSAX MAIL n. 99/24: GRB ALERT: GRB990907
  78. GRB990806 BeppoSAX follow up
  79. GRB 990806, Optical Observations
  80. GRB 990806, optical observations
  81. GRB 990806, Optical Observations
  82. GRB990806 UBVRIJHK observations
  83. BeppoSAX ALERT GRB990806: Summer GRB
  84. VLT spectrum of GRB990712
  85. Updated Astrometry for the IR Counterpart of GRB990705
  86. Infrared and Optical Observations of GRB990705
  87. GRB990704 radio and optical observations
  88. GRB 990704 X-ray Observations
  89. GRB990705: Intriguing Positional Coincidences
  90. Optical Observations of GRB990627
  91. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  92. GRB 990506 optical observation
  93. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  94. BeppoSAX: A new fast X-ray transient
  95. GRB 990506 R band observations
  96. VLT spectrum of GRB990510
  97. GRB 990510: Broad Band Break
  98. GRB 990510: BeppoSAX/GRBM observations
  99. GRB990510 optical observations
  100. GRB 990510 optical observations

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