Suspected Variables in AAVSO Star Fields

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Suspected VariablesinAAVSO Star Fields

• American Association of Variable Star Observers
• 96th Spring Meeting, Calgary, AB
• June 29 July 2, 2007
• Richard Huziak ltHUZgt
• Saskatoon, Saskatchewan, Canada

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What is the Suspected Variable Star Program?

• identifies stars in the AAVSO Validation file
  that are suspected by some observer of being
  variable
• investigates these stars to determine if they
  are indeed variable.
• an unofficial program. The AAVSO hosts the
  Suspects Database spreadsheets
• the Suspects Database has been of benefit when
  maintaining the Validation File and is useful
  when sequences are questioned.
• http//www.aavso.org/observing/charts/suspect.shtm
  l

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Suspects in the Validation File

• mostly labelled with lettered suffixes on the
  validation file
• not all suspected stars are marked on AAVSO
  charts
• Reasons the stars are suspected
• observers at eyepiece sees comp star at wrong
  magnitude
• secondary stars in the field suspected from
  research of the primary variable
• NSV stars added in older chart revs
• may be sequence errors

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What is the Suspected Variable Star Program?

• SUSPECT
• PROGRAM
• PART I
• Identification
• ID all suspects with GSC names
• Provide positions
• Provide information
• Provide cross references to see if these have
  been recognized as variable already
• Has taken 4 years and is 95 complete.

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• So..
• take a normal AAVSO chart.

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• .and add all suspects other field variables

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• Problems when suspects are variable!
• some stars are comparison stars!
• time waster for CCD photometrists and sometimes
  for visual observers
• sequence confusion
• rediscovery of the suspect since they are rarely
  marked.
• There are 1930 suspects in Validation!

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SUSPECT PROGRAM PART II

• Are the Suspects Variable?
• The answer is found through
• data-mining (TASS, ASAS-3, SIMBAD..)
• CCD imaging analysis
• Goals of the Suspects Program
• image all 1930 suspect variables to determine
  variability of suspects and
• (we didnt expect) to weed out all variable
  comparison stars

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My Equipment ltimage U of S Variable Star Research
Lab

• U of Sask
• loaner equipment

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Methodology(Prediscovery)

• must be CCD imaged visual cannot detect most
  suspects unequivocally (found by experience)
• minimum 4-hour time series per field
• minimum 12 nights of spot hits
• minimum 5 images per spot-hit session to remove
  imaging errors (cosmic rays, flat issues, glare,
  etc)
• imaged in 2 consecutive seasons
• ALL comparison stars reduced against ONE STAR of
  a magnitude value assumed from the visual chart
  (most sequences not calibrated)
• up to 20 field stars are monitored as controls
• all stars with Harvard Designators have data
  submitted to the AAVSO dbase typically the Mira
  star all suspects in the field

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Methodology(Post-discovery)

• If we discover anything
• monitoring of stars in time frame required to
  characterize typically EVERY night for all new
  stars no matter what type
• enter to VSX ( CHET??) a.s.a.p. (to stop
  re-discovery wasted time by others)
• write up in IBVS, JAAVSO, PASP, eventually..

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093934CRRab starPer 0.65540dRange12.68 -
13.25V

• Examples
• R LMi

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• Examples
• TV Her

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• Examples
• TV Her

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• 023260B
• NSVS data exists (0240202610717)
• EA X-ray (RS CVn)
• Per. 2.2376151d
• Range 10.2 - 11.1V
• Secondary ecl. is total

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• Examples
• KM Cyg

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• Examples
• KM Cyg

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• Examples
• S Cyg

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• Examples
• S Cyg

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• Examples
• SS Cyg

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• Examples
• SS Cyg

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WZ And
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WZ And
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Before You Panic Say Our Charts
Suck!.. Sometimes size (of variation) DOESNT
MATTER if a low-amplitude star is found, it
does not affect visual observers /
charts HOWEVER, CCD guys are using the visual
charts all the time because that is all there is!
We do not want CCD guys to waste their time
rediscovering known variables, so
somehow.. charts need to reflect what has been
discovered and what is suspected. This may be
possible when VSP comes on-line.
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Results Statistiscs

• 28 months into the imaging program
• 105 fields imaged (with sufficient data)
• 36 fields analysed (containing 68 suspects)
• 17 confirmations of variable suspects (25)
• 44 additional NEW variables
• 34 new suspected variables (perpetual motion
  machine)
• 100,000 frames taken
• only 15 of frames for the past year have been
  analysed this takes time, folks!
• program to date concentrates on highest
  probability stars

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• BYPRODUCTS gtgtgtgtgtgtgtgt

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S Cyg long-term accurate curve

• Long-term, high quality, consistent data, reduced
  against the same comp star.

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Other Accurate Curves of New Field Variables
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Need A Program? YOU ARE ALREADY OBSERVING THE
FIELD VARIABLES, SO START REDUCING SUBMITTING
FOR THE SUSPECTS! Suspects Program 33 years
long (_at_ current rate of imaging processing)
HUZ 50 years old now H
UZ 83 when done New observers always
welcome! Current active helpers Rick Huziak
(HUZ) Vance Petriew (PVA) Michael Koppelman
(KMP) Walter Cooney (COO) ltreserved for your namegt
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Acknowledgements CCD cameras, telescopes and
computers used by Rick Huziak have been provide
under the Sleaford Observatory Partnership
Agreement by Stan Shadick of the Department of
Physics Engineering Physics, University of
Saskatchewan Charts and data for some of the
variable star graphs are provided courtesy the
AAVSO International Variable Star Database Some
light curves compiled by M. Koppelman (KMP)
Vance Petriew (PVA)