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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').

10050 results found.

  1. SGR1900+14: A Burst Localized by HETE
  2. SGR1806-20: A Second, Intense Burst Localized by HETE
  3. SGR1806-20: Localization by HETE
  4. GRB010214, optical observations
  5. GRB Observation Report
  6. REVISED LOCATION OF GRB010326A
  7. GRB010326B: Localization by HETE (2nd GRB for this date)
  8. GRB010326: Refined Localization by HETE
  9. GRB010326: Localization by HETE
  10. Optical Observations of GRB 010324
  11. GRB 010222 - HEGRA GeV/TeV Observations
  12. GRB010222, possible increase of optical decay slope
  13. GRB 010220: Near-IR Observations
  14. GRB 010222: Near-IR Observations
  15. GRB010214, candidate optical afterglow
  16. GRB010214, optical observations
  17. J-Band Observation of GRB 010214.
  18. Possible InfraRed Transient of GRB 010214.
  19. GRB010214 Optical Observation
  20. GRB010213 detected by HETE
  21. GRB010126, TNG R-band observations
  22. Optical Observations of GRB 001018 at Keck
  23. H band observation of GRB 001212
  24. GRB 001109: deep JHK upper limits
  25. CORRECTION to XMM-Newton observation of GRB001025
  26. XMM-Newton observation of GRB001025
  27. V,R,I band observations of GRB000926
  28. The Likely Optical/Infrared Afterglow of GRB 001011
  29. Public availability of BeppoSAX data of GRB000926
  30. GRB000926: X-ray afterglow by BeppoSAX: revised fluxes (fwd)
  31. GRB 000926, Optical Decay
  32. GRB 000926, Optical Observations
  33. J and K band observations of GRB 000926
  34. GRB 000926, Optical Observation
  35. Optical candidate for GRB000926
  36. GRB000830, TNG B-band observations
  37. GRB000210, Optical observations
  38. Chandra Position of GRB000210
  39. GRB000812, TNG R-band observations
  40. GRB000801, VLT-Antu R-band observations
  41. GRB000630, optical observations
  42. GRB000418, HST/STIS Observations
  43. GRB000620, optical observations
  44. GRB000615: H-band observations
  45. GRB000620 Optical observations
  46. GRB000607, optical observations
  47. GRB000616 optical observations
  48. GRB 000615: NIR observations
  49. Optical Follow-up of GRB000529 Error Box
  50. GRB000528, optical observations at ESO
  51. Re: GRB000508B : Optical observations
  52. GRB 000424 Optical Observations
  53. GRB 000418, Optical Observation
  54. GRB000424 Optical Observations
  55. GRB 000418, Optical Observation
  56. GRB 000418, Optical Observation
  57. BeppoSAX GRB000424
  58. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  59. GRB 000301C: Optical Spectrum and Redshift
  60. GRB 000301C: Optical Spectrum and Redshift
  61. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  62. GRB000301C, optical R-band observations
  63. GRB 000301C: K' Observations
  64. GRB000301C - Host galaxy not detected in R (?)
  65. GRB 000301c near-IR observations
  66. GRB 000301C, Optical Color
  67. GRB 000301C, Optical Observation
  68. GRB 000301C, Optical Observation
  69. GRB 000115 Optical observations
  70. GRB 000115 Optical observations
  71. GRB 991216: J band spectrophotometry
  72. GRB991217/SAX J2303.2+0015, optical observations
  73. Chandra observation of the X-ray afterglow of GRB991216
  74. GRB 991208 Keck Spectroscopy
  75. GRB 991208 Infrared Detection
  76. GRB 991216: Comparison with DPOSS images
  77. R-band Observations of GRB991208 at TNG
  78. GRB991208, optical observations
  79. Optical Observations of GRB991105
  80. GRB991106, optical observation at SAO-RAS
  81. Revised BeppoSAX WFC position of GRB991105
  82. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
  83. GRB 991014, radio observations
  84. GRB 991014, Optical Observations
  85. Optical Observations of GRB990907
  86. BeppoSAX MAIL n. 99/24: GRB ALERT: GRB990907
  87. GRB990806 BeppoSAX follow up
  88. GRB 990806, Optical Observations
  89. GRB 990806, optical observations
  90. GRB 990806, Optical Observations
  91. GRB990806 UBVRIJHK observations
  92. BeppoSAX ALERT GRB990806: Summer GRB
  93. VLT spectrum of GRB990712
  94. Updated Astrometry for the IR Counterpart of GRB990705
  95. Infrared and Optical Observations of GRB990705
  96. GRB990704 radio and optical observations
  97. GRB 990704 X-ray Observations
  98. GRB990705: Intriguing Positional Coincidences
  99. Optical Observations of GRB990627
  100. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations

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