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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"

26040 results found.

  1. SN 2003jd (SN/GRB?) - possible association with GRB 030929
  2. GRB 031026 (=H2882): Evidence for High Redshift from Prompt
  3. GRB030329: radio observations at RT-22 (CrAO)
  4. XRF 030723: Detection of the likely host galaxy
  5. GRB030913: Subaru Optical Observations
  6. GRB030913, candidate afterglow observations
  7. GRB030913: AAVSO optical observations
  8. GRB030913 (=H2849): Confirmation of the Flight Localization
  9. Magellan Observations of GRB030725 (=H2779)
  10. GRB030913 (=H2849): A GRB Possibly Localized by HETE
  11. GRB 030824: Candidate Afterglow (or Variable/Flare Star?)
  12. GRB 021206 Optical Observations
  13. XRF030723(=H2777): Chandra Fading X-ray Afterglow Confirmed
  14. XRF 030723: Detection of a rebrightening in the optical afterglow
  15. GRB030725: Optical observations
  16. XRF030723, BVRcIc field photometry update
  17. XRF030723: Re-analysis of ROTSE-III early images
  18. GRB030725, optical transient observations
  19. XRF030723 Radio Observations
  20. XRF030723(=H2777): Chandra Observations
  21. XRF 030723: VLT spectra
  22. GRBlog: Compilation of all GCN Circ. data
  23. GRB030329: second XMM-Newton observation
  24. GRB030418: R optical observations
  25. GRB 021206, Radio afterglow candidate
  26. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  27. GRB 030528: Infrared Observations and the Proposed IR Counterpart
  28. GRB 030528: Optical Observations
  29. GRB 030528: tentative NIR counterpart
  30. GRB030329, further radio observations at GMRT
  31. GRB 030519B: optical observations.
  32. GRB 030329: optical observations
  33. GRB 030329: Correction to GCN 2254
  34. GRB 030329: Optical Observations
  35. GRB 021004: HST observations
  36. GRB030324: Further Observations of the Candidate Optical Afterglow
  37. GRB 030418: Second Epoch Optical Observations with Magellan
  38. GRB 030329: Optical limit (contemporaneous imaging)
  39. GRB030329: RTT150 optical observations
  40. GRB 030329: Optical limit (contemporaneous photography)
  41. GRB 030429: Redshift of neighbor galaxy
  42. GRB030429: RTT150 optical observations, a possible host galaxy
  43. GRB030329: RTT150 optical observations and upper limit for a host
  44. GRB 030329: all-sky CCD images by K. Shiokawa immediately after the burst
  45. GRB030329: RTT150 optical observations and upper limit for a host
  46. GRB 030429: redshift from VLT spectroscopy
  47. GRB 030429: IR photometry with IRSF/SIRIUS
  48. GRB 030329 Optical Observations
  49. GRB030501: TAROT candidate afterglow present in archival images
  50. GRB 030429: confirmation of afterglow candidate
  51. GRB 030329 Oprical observations in Rozhen observatory
  52. GRB 030324: Radio Observations
  53. SNeIa AS THE POSSIBLE PROGENITORS OF SHORT-DURATION GRBs.
  54. GRB 030329: Spectral Evolution of SN 2003dh
  55. Optical Observations of GRB 030418 with Magellan
  56. GRB 030329: optical spectropolarimetry at VLT
  57. GRB 030329: wide-field photograph by R. Tamura 1 hr after the burst
  58. GRB030418: Kiso near infrared observations
  59. GRB 030418: Optical afterglow
  60. GRB 030418: Finder for afterglow candidate
  61. GRB 030418: Optical afterglow candidate
  62. GRB030329, UBVRI polarimetry, R-polarization
  63. GRB 030329: SARA Optical Observations
  64. GRB030329: VR Photometry at TNG
  65. GRB030324: Candidate Optical Afterglow (Erratum)
  66. GRB030324: Candidate Optical Afterglow
  67. GRB 030329 Rc observations
  68. Superluminal motion in GRB 030329 (Correction)
  69. Superluminal motion in GRB 030329
  70. GRB 030329 and SN 2003dh
  71. GRB 030329 VLBA Observations
  72. GRB 030329: BVRI photometry at Asiago
  73. GRB 030329: Supernova Confirmed
  74. GRB030329: RTT150 optical observations
  75. GRB030329: Near Infrared Observations at Gunma
  76. Kiso observation of the GRB030329 at April 6
  77. GRB 030329 Optical observations
  78. GRB 030329, color evolution
  79. GRB 030329: possible color change
  80. GRB030329: RTT150 optical observations
  81. GRB 030329: Supernova Spectrum Emerging
  82. GRB030329: Kiso B and R band observations
  83. GRB030329: RTT150 optical observation
  84. GRB 030329: SARA Optical Observations
  85. GRB 030329: SARA Optical Observations
  86. GRB030329, fading resumes
  87. GRB 030329, Optical observations
  88. GRB 030329, nearby galaxies
  89. GRB030329 Radio 23/43/90 GHz observations at Nobeyama
  90. GRB 030329: Sub-millimeter detection
  91. GRB 030329: SARA Optical Observations
  92. GRB 030329: SARA Optical Observations
  93. GRB030329, new UBVRcIc field photometry
  94. GRB 030329, light curve and SN prediction
  95. GRB030329: optical observations at Tokyo Tech
  96. GRB 030329: optical observations
  97. GRB030329: multiple re-brightening phases
  98. GRB030328: Full Observation, X-ray Fading and Spectrum Measured
  99. GRB 030329 , SPM optical observations
  100. Further AAVSO V,B,R observations of GRB030329

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