Bohdans idea of astronomy with small telescopes'

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Bohdans idea of astronomy with small telescopes.

• Do we need them?

Grzegorz Pojmanski Warsaw University
Astronomical Observatory
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Moon,Mercury - 1978
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Superluminal motion -1978
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PC Personal Computer - 1981
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PC Personal Telescope - 1981
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PT Personal Telescope 1995
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PT Personal Telescope 1995

• BP in Warsaw fall 1995
• Impact of OGLE massive photometry results
• Wide-angle survey objectives
• Observing scenarios
• Idea of amateur collaboration
• Existing and developing projects
• Niche for the All Sky Automated Survey
• low cost wide-angle monitoring survey.

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Paczynski 1996 - 12-th IAU Coll

• The Future of the Massive Variability Searches

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Background

• Photographic sky surveys/patrols
• wide-field - using Schmidt cameras
• Palomar Atlas
• abandoned, but some gain new (scanned) life
• Harvard College Observatory Astronomical Plate
  Stacks (500,000)
• Hipparcos
• short baseline, brightest stars
• (Ambitious) existing CCD Surveys
• 2MASS, SDSS, 2dF
• deep, one epoch, selected fileds

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Objectives variable stars

• Among 5 mln stars there should be about
• 50,000 periodic variables
• 200,000 less regular or long-term ones
• Only a few percent of these were recognized so
  far
• GCVS incompleteness starts at 8-th mag.
• Important for calibration of basic stellar
  parameters
• e.g. distances, using bright detached systems
  (requires spectroscopy)
• asteroseismology
• or for statistical investigation (unbiased data)
  of
• stellar structure and evolution
• galactic structure
• or as input to contemporary space missions (e.g.
  Kepler)
• Investigated time scales restricted mostly to
  hours weeks range

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Objectives - photometry

• What we have is
• Hipparcos/Tycho
• reasonable B V photometry (5-10 mag)
• literature compiled I magnitudes
• 2MASS
• J,H,K survey
• What we need is
• survey I photometry for bright stars
• reasonable, survey V,I in 10-15 range
• used for other survey calibration
• used by narrow field CCD photometry projects
• accurate relative photometry
• for small amplitude variability, transits, etc.

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Objectives alerts (EWS)

• Triggering prompt follow-up observations of
• Rare phenomena of astrophysical interest
• eruptions (DN, N, SN)
• microlensing events
• occultations, transits
• GRB optical counterparts
• afterglows (e.g. ROTSE GRB990123)
• pre-flashes
• Other optical transients
• Bohdans idea of fast flashes of unknown origin
• Asteroids (including NEOs)
• Comets

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Objectives on-line archive

• catalog of all sources V,I,R
• mean brightness, dispersion
• catalog of variable objects
• calssification, periods, amplitudes, ephemeris
• light curves on request
• e.g. checking object status on past dates
• catalog of special events (e.g. novae, dwarf
  novae, optical transients)
• catalog of asteroid and comet observations

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PT Personal Telescope 1995

• BP in Warsaw fall 1995
• Impact of OGLE massive photometry results
• Wide-angle survey objectives
• Observing scenarios
• Idea of amateur collaboration
• Existing and developing projects
• Niche for the All Sky Automated Survey
• low cost wide-angle monitoring survey.

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Survey properties

• ) f/3 optics, sky 22m/arcsec2, exposure time
  to reach sky 2-3 min

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Original BPs idea - Barn door design
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Final setup - horseshoe design

• Based on AutoScope design
• Flexible in operation
• Quite precise
• Portable
• Unexpensive

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Original BPs idea - Barn door design
Lap top model -)

• Micro Telescope
• F4.5 mm, f/1.4
• FOV 90x60 deg
• I lt 7.0 mag

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Survey Instruments

• Assumption - Low cost project
• prototype 1997 - ASAS-1,2 10 k
• custom made mount
• 768x512 Pictor (MEADE) camera
• 135 mm 2 x 3 deg
• 300 sq. deg several times per night
• upgrade 2000 ASAS-3 70 k
• 200 mm 8.5 x 8.5 deg, V, I
• 50 mm 36 x 36 deg, R
• 750 mm 2 x 2 deg, I
• 4 x 2K2 AP-10 (Apogee) cameras
• 30,000 sq. deg. once per 1-3 nights
• upgrade 2006 ASAS-N 15 k
• 2 x 200/2.0 (V, I)

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PT Personal Telescope 1995

• BP in Warsaw fall 1995
• Impact of OGLE massive photometry results
• Wide-angle survey objectives
• Observing scenarios
• Idea of amateur collaboration
• Existing and developing projects
• Niche for the All Sky Automated Survey
• low cost wide-angle monitoring survey.

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The Amateur Sky Survey 1994

• Tom Droege , Batavia, retired engeneer from
  Fermilab

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The Amateur Sky Survey - 1995
Mark I,II
Mark IV
Mark III
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Mark III - tenxcat (also _at_Vizier)

• Catalog of 367,241 stars in V, I (some R), N30
• Covers 2.5 years
• Photometric precision 0.03 mag (V) to 0.09 mag
  (I) .
• 10 mln measurements in V, I-bands,

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TASS- Mark-IV

• Status as of 9/19/07 612 AM
• Number of observations 206,791,276
• Number of stars 10,208,268

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AAVSOAmerican Association of Variable Star
Observers
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VSNET - Variable Star Network
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PT Personal Telescope 1995

• BP in Warsaw fall 1995
• Impact of OGLE massive photometry results
• Wide-angle survey objectives
• Observing scenarios
• Idea of amateur collaboration
• Existing and developing projects
• Niche for the All Sky Automated Survey
• low cost wide-angle monitoring survey.

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Existing surveys

• LINEAR - The Lincoln Near Earth Asteroid
  Research
• gt400,000 asteroids, gt 500 NEOs
• SPACEWATCH, LPL, U.Arizona
• telescopes 1.8m 0.9m on Kitt Peak
• gt600 NEOs. gt30 comets, gt10 TNOs
• TAROT - Télescopes à Action Rapide pour les
  Objets Transitoires, Obs. de Haute Provence
• Farest known GRB 050904 at z6.3
• ... many, many more

TAROT image of the farest known GRB 050904 at
z6.3
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CONCAM

• Robert Nemiroff

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ROTSE

• Robotic Optical Transient Search Experiment
• Carl Akerlof
• U. Michigan, LANL, LLNL
• camera 4x (200/1.8 2048x2048 CCD)

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ROTSE GRB990123
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ROTSE I - NSVS

• Northern Sky Variability Survey
• Przemek Wozniak
• mag 8-15.5, no filter,
• 15 mln stars, 100-500 measurements
• SkyDot interface

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HAT

• Gaspar Bakos, 1998
• N-ASAS ? HAT-1,

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HAT planets

• HAT-P-1b 2003/2004 ApJ 656, 552, 2007 February
  10

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HAT-P-2b, HAT-P-3b
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PT Personal Telescope 1995

• BP in Warsaw fall 1995
• Impact of OGLE massive photometry results
• Wide-angle survey objectives
• Observing scenarios
• Idea of amateur collaboration
• Existing and developing projects
• Niche for the All Sky Automated Survey
• low cost wide-angle monitoring survey.

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ASAS-1 in Las Campanas Observatory - 1997
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ASAS-2 1998
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ASAS-2 - 1998

• In 10 astrograph dome
• Fully automated
• 2 years of observation
• 50 fields, 300 sq. deg
• 150,000 stars
• 50 mln measurements
• 5,000 variable stars

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ASAS-3 2000
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ASAS-3 2002
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2004
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ASAS-N 2006 Haleakala, Maui
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Data processing and analysis pipeline

• Observer
• Interruptable e.g. by GCN (HETE, SWIFT, etc.)
• Default CCD processing
• darks, flats
• Aperture photometry
• 2,3,4,5,6 pixel diameter
• accuracy of 0.01 _at_ 9 mag, 0.3 _at_ 14 mag
• Astrometry
• using ACT catalog
• accuracy 3 arcsec.
• Catalog - standarized photometry
• against Tycho V-band data
• against I (JHKV) calibration based on
  2MASSTycho
• accuracy 0.05 -...(0.2) mag.
• Alert system
• against ASAS Catalog
• human verification required (99 false alerts _at_
  12. mag)

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ASAS Interface
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Variability search

• Semi-automatic
• automated selection of candidates
• large dispersion on light curve
• tested above 95 percentile
• individual outstanding points
• high signal in power spectrum
• laborious visual verification
• automated classification of
• strictly periodic light curves.

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ASAS Variables
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Automated classification
a4
b4
b4
eclipsing
eclipsing
contact
pulsating
detached
pulsating
semi-detached
a2
b2
a4
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Eclipsing binaries
contact
semi-detached
detached
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Pulsating stars
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Variable stars over 75 of the sky 0h-24h,
dlt28o
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ASAS vs. GCVS
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ASAS Alert System

• Observing mode
• 3 x 1 minute
• shift-reject-add
• makes use of inperfect tracking
• creates maps of events (cosmics, satellites,
  etc.)
• fast optical transients (1min) are discarded
• Trigger events
• automated check procedure
• planets, planetoids, comets (MPChecker)
• variable stars (GCVS, ASAS)
• ghosts, reflections
• new objects entering the catalog
• transient hot pixels
• close / blended stars
• true sources Mira stars, CVs, Novae, asteroids,
  comets
• substantial change of brightness
• brightening flares, eruptions, blended cases
• fading EA eclipsers, other variables

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Asteroids
(170)Maria
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ASAS 171251-3056.6 (Nova)
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ASAS 181932-2836.6 (Nova)
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C/2004 R2 (ASAS)
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C/2006 A1
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GRB follow-up

• 166 triggers followed in 2001-2006
• 50 real-time
• response time 1-2 minutes
• 2/3 HETE
• 1/3 SWIFT
• 60 long delay (1-12 h)
• 1/3 HETE
• 2/3 SWIFT

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GRB follow-up

• No bright (lt12m) afterglows detected
• No check for faint counterparts was done
• Data available for further processing

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LMC and SMC Cepheids

• Pietrukowicz 2001
• astroph/0108407

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b Cephei stars

• 102 new bCep stars
• 180 more from recent search
• 4 in eclipsing systems

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Discovery of a Very Bright, Nearby Gravitational
Microlensing Event

• Gaudi et al. 2007, astroph 0703125
• V11,4,
• d1 kpc,
• SpA0V

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Nearby Supernovae

• SN 2003hv
• detected on 2883.85 _at_12.9 (9 days before
  discovery)
• SN 2005af
• detected on 3394.86 _at_ 13.2 (16 days before
  discovery)
• SN 2005df
• detected on 3590.88812 _at_ 12.76 (3 days after
  discovery),

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Nearby supernovae

• SN 2007bk V_max 15.7 mag
• Discovery - 18 Apr 2007
• ASAS - 06-26 Mar 2007

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Eclipsing binaries

• Paczynski et al, 2006 (0601026)
• Eclipsing binaries in ASAS catalog
• 11099 stars
• relaxation oscillations, Kozai cycle

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Eclipsing binaries
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Contact binaries

• Rucinski 2006 (0602045)
• Luminosity function of contact binaries based on
  the ASAS survey
• 3373 systems with Plt0.562, 8ltVlt13
• spatial density 0.2 against stars on MS

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Cefeid 1O/2O

• Beltrame, Poretti, 2002, (0203078)
• HD 304373, the second case of 1O/2O doublemode
  Cepheid in the Galaxy.
• P10.9220, P2/P10.8058
• second one CO Aur
• P11.78303, P2/P10.8008

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Dwarf Novae

• Templeton, et al. 2005 (0510078)
• The Recently-Discovered Dwarf Nova System ASAS
  0025111217.2 A New WZ Sagittae Star
• Sep 2004
• short period binary, superhumps 81.9 min

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Cataclysmic binaries

• Patterson, Thorstensen , Kemp, 2005 (0502392)
• Pulsations, boundary layers and period bounce in
  the cataclysmic variable 1255266
• EUV source (ROSAT)
• DA with emisison lines

ASAS 1536160839.1 (2004)
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Summary

• ASAS-1,2 prototype for 10,000
• capable to monitor 100 sq. deg / h
• ASAS-3 4 cameras, 60,000
• capable to monitor 4,000 sq. deg / h
• half of the sky 2 times per night
• ASAS-N V,I for 15,000
• V system alone fully automated
• 16,000 sq. deg / night
• On-line catlaog
• 5 minute delay
• data, light curves for
• 20,000,000 stars monitored
• 2,300,000,000 masurements
• gt50,000 variables (only... but will be more)
• I system catalog is ready
• 900,000 candidates for variables waiting for
  verification
• GRB follow-up running, but not competitive