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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').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

36152 results found.

  1. GRB 030329: wide-field photograph by R. Tamura 1 hr after the burst
  2. GRB030329: optical polarization
  3. IPN triangulation of GRB030422 (two large error boxes)
  4. GRB 030329 3.5 and 6 cm radio observations at RTF-32 telescope
  5. IPN triangulation of GRB030421 (annulus)
  6. MASTER:optical observations GRB030418
  7. MASTER:optical observations probable GRB030414
  8. GRB030329: 444 AAVSO Measurements
  9. IPN triangulation of GRB030419 (annulus)
  10. MASTER:optical observations GRB030416
  11. ROTSE-III prompt optical detections of GRB 030418
  12. GRB030418: Upper limits from recent and historical observations.
  13. GRB030418: Kiso near infrared observations
  14. GRB 030418: Optical afterglow
  15. GRB 030418: Finder for afterglow candidate
  16. GRB 030418: Optical afterglow candidate
  17. GRB 030329 OT position
  18. OT GRB 030329: early UBVRcIc spectral evolution
  19. GRB030329, UBVRI polarimetry, R-polarization
  20. GRB 030329: SARA Optical Observations
  21. OT GRB 030329: early spectrum
  22. GRB030329: VR Photometry at TNG
  23. GRB030324: Candidate Optical Afterglow (Erratum)
  24. GRB030324: Candidate Optical Afterglow
  25. IPN triangulation of GRB030414 (small error box)
  26. GRB 030413: Optical Observations
  27. GRB 030329 Rc observations
  28. IPN triangulation of GRB030413 (small error box)
  29. IPN triangulation of GRB030410 (annulus)
  30. Superluminal motion in GRB 030329 (Correction)
  31. Superluminal motion in GRB 030329
  32. GRB 030329 and SN 2003dh
  33. GRB030329, optical position
  34. GRB 030329 VLBA Observations
  35. IPN triangulation of GRB030406 (small error box)
  36. IPN triangulation of GRB050403 (small error box)
  37. IPN triangulation of GRB030403 (annulus)
  38. GRB 030329: BVRI photometry at Asiago
  39. GRB 030329, light curve flattens
  40. GRB 030329: VLT V-band photometry
  41. If the SN/GRB connection confirmed
  42. GRB 030329: Supernova Confirmed
  43. GRB030329: RTT150 optical observations
  44. GRB030329: Near Infrared Observations at Gunma
  45. GRB030329: HET spectroscopic monitoring
  46. Kiso observation of the GRB030329 at April 6
  47. GRB 030329, color evolution
  48. GRB030328, UBVRcIc field photometry
  49. GRB 030329 Optical observations
  50. GRB 030329, color evolution
  51. GRB 030329: possible color change
  52. GRB030329: RTT150 optical observations
  53. GRB 030329: Supernova Spectrum Emerging
  54. GRB030329: Kiso B and R band observations
  55. GRB030329: RTT150 optical observation
  56. GRB030329: More AAVSO VR obs
  57. GRB030328: R upper limit after 6 hours by MASTER
  58. GRB 030329: BV photographic observations
  59. GRB 030329: SARA Optical Observations
  60. GRB 030329: SARA Optical Observations
  61. GRB030329, fading resumes
  62. GRB 030329, BVRI photometry
  63. SDSS 0.5m PT observations of GRB030329 (correction)
  64. SDSS 0.5m PT observations of GRB030329
  65. GRB 030329, Optical observations
  66. GRB 030329, nearby galaxies
  67. GRB030329, cessation of fading
  68. GRB030329 Radio 23/43/90 GHz observations at Nobeyama
  69. GRB 030329: Sub-millimeter detection
  70. GRB 030329: SARA Optical Observations
  71. GRB 030329: SARA Optical Observations
  72. OT GRB light curves and SN predictions
  73. GRB030329, optical observation
  74. GRB030329, new UBVRcIc field photometry
  75. GRB 030329, light curve and SN prediction
  76. GRB030329: optical observations at Tokyo Tech
  77. GRB 030329: optical observations
  78. GRB030329: multiple re-brightening phases
  79. GRB 030329, BRI photometry
  80. GRB 030329 , SPM optical observations
  81. GRB 030329: Radio observations at GMRT
  82. Further AAVSO V,B,R observations of GRB030329
  83. GRB 030329: Additional Mt. Laguna Optical Observations
  84. GRB 030329: SARA Optical Observations
  85. GRB 030329: Observations with ANDICAM
  86. GRB030329: further optical photometry and evidence for a light curve discontinuity
  87. GRB 030329: Correction to GCN 2056
  88. GRB 030329: fitting parameters and re-brightening
  89. GRB 030329: KAIT optical photometry
  90. GRB030329 Further RBO Optical Observations
  91. triangulation of GRB 030331 (single error box)
  92. GRB030329 - OT rebrightens
  93. GRB 030329: SARA Optical Observations
  94. AAVSO V & R observations of GRB030329
  95. IPN triangulation of GRB030331 (annulus)
  96. GRB 030329: optical observations
  97. IPN triangulation of GRB030329b (large error box)
  98. GRB 030329: beginning of the new fading phase in optical band
  99. GRB 030329, optical spectroscopy
  100. GRB 030329: fading X-ray afterglow with RXTE

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