AQUEYE: SCIENTIFIC TARGETS

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AQUEYESCIENTIFIC TARGETS
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Aqueye ultrafast photometer

• Exploitation of high time resolution to study
  high speed astrophysical phenomena in
• Pulsars
• Cataclysmic variables
• X-ray binaries
• Pulsating white dwarfs
• Pulsating neutron stars
• Flare stars
• Planetary nebulae
• Stars with transiting exoplanets

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PULSAR

• Formation by a supernova explosion

extremely high rotational velocity (periods
range from 1.5 ms to 8.5 s )
intense magnetic field (typically in the range of
108 - 1012 gauss )

• Neutron star

• extremely
• high density

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• Pulsars are highly magnetized rotating neutron
  stars
• Accelerated charged particles

emissions in radio, visible, x-ray and ?-ray
domains
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• Lighthouse effect
• extraordinarily rapid and stable rotation

pulsed nature
very regular rotation period (the regularity of
pulsation is as precise as an atomic clock)
pulsars as useful instrument for Aqueyes
calibration
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Crab Pulsar

• The first pulsar discovered (1968)
• Remnant of AD1054 supernova
• It lies in the Crab Nebula (M1)
• Period P 33 ms
• Delay 36ns /day
• The brightest optical pulsar we know
• Double pulse per rotation in visible, X-ray and
  ?-ray domains
• The most energetic pulsar we know
• Right ascension 05h 34m 31.97s
• Declination 22 00 52.1

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CATACLYSMIC VARIABLES

• CVs binary systems in which a late-type
  secondary star fills the Roche lobe and transfers
  matter onto a white dwarf (WF)

CLASSIFICATION ACCORDING TO THE MAGNETIC
BEHAVIOUR
1) non-magnetic systems
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2) Intermediate- Polars (DQ Herculis stars)
3) Polars (AM herculis stars)
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CVs flickering

• FLICKERING stochastic brightness variations
• Time scale dozen minutes less than a
  second
• Amplitudes a few tenths of magnitude
  magnitude scale

flickering as a continuous series of overlapping
flares and bursts in the light curves of CVs with
random variability
Fig lightcurve of V709 Cas (Tamburini et al., in
preparation)
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WHY IS FLICKERING IMPORTANT? 1) its a
fundamental signature of accretion processes 2)
it represents a significant fraction of the total
luminosity of the source
OPEN QUESTIONS 1) whats the exact physical
nature? 2) is flickering a self-similar process
also at very small scales?
short time-scale down to which flickering
is still self-similar vital information about
the driving mechanism behind flickering underst
anding the physics occurring at much shorter
time-scales
HIGH SPEED PHOTOMETRY
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4-6 APRIL

• Object RA(J2000) Dec(J2000) Type ltmgt
  ?morb Pspin (s) Porb (h)
• ST LMi 11 05 39.8 25 06 28.9 P 15.1 (B)
  1.8 (B) - 1.898
• YY Dra 11 43 38.3 71 41 20.4 IP 14.0 (V)
  2.0 (V) 529.31 3.969
• AM CV 12 34 54.6 37 37 43.4 NL 14.1 (V)
  0.1 (V) - 0.286 (17.1 min)
• GP Com 13 05 42.9 18 01 03 NL 15.6 (B)
  0.4 (B) - 0.776 (46.6 min)
• CT Ser 15 45 39.0 14 22 32.7 N 16.3 (V)
  0.3 (V) - 4.68
• DQ Her 18 07 30.3 45 51 32.6 IP 15.2 (V)
  3.5 (V) 71.066 4.647
• V533 Her 18 14 20.3 41
  51 21.3 N 14.4 (V) 0.8 (V) 63.63 3.528
• AM Her 18 16 13.3 49 52 04.2 P 12.0 (V)
  1.5 (V) - 3.094
• Object RA(J2000) Dec(J2000) Type ltmgt
  ?morb Pspin (s) Porb (h)

8-12 OCTOBER
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22-27 OCTOBER

• Object RA(J2000) Dec(J2000) Type ltmgt ?morb Pspin
  (s) Porb (h)
• RX And 01 04 35.6 41 17 58.0 DN 14.0 (V) 1.5
  (V) - 5.037
• XY Ari 02 56 09.0 19 26 29 IP 13.1 (K) 0.4
  (K) 206.298 6.065
• GK Per 03 31 11.8 43 54 16.8 IP 12.8 (V) 0.9
  (V) 351.332 47.923
• V1159 Ori 05 28
  59.5 -03 33 52.8 DN 13.6 (V) 1.8 (V) - 1.492
• V405 Aur 05 57 59.3 53
  53 44.9 IP 13.9 (V) 0.7 (V) 545.455 4.143
• KR Aur 06 15 43.9 28 35 08.9 NL 11.3 (B) 2.3
  (B) - 3.907
• BG CMi 07 31 29.0 09 56 22.6 IP 14.3 (V) 1.1
  (V) 847.03 3.234
• PQ Gem 07 51 17.4 14 44 24.6 IP 14.0 (V) 0.5
  (V) 833.42 5.193
• EI UMa 08 38 22.0 48 38 01.7 DN 14.8 (V) 1.2
  (V) 741.6 6.434
• BK Lyn 09 20 11.2 33 56 42.6 NL 14.5 (V) 2.4
  (V) - 1.800
• YY Dra 11 43 38.3 71 41 20.4 IP 14.0 (V) 2.0
  (V) 529.31 3.969
• P polar, IP intermediate polar, N nova, NL
  nova-like, DN dwarf nova

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QPOs (Quasi Periodic Oscillations)

• QPOs quasi coherent variabilities about certain
  frequencies
• Main sources Low Mass X-Ray Binaries
• Probable emission s cause shocked wave created
  on the accretion disk
• Why are we interested in?

to understand the innermost regions of accretion
disks of the central compact objects
What sort of variation with time could cause a
QPO?
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PULSATING WHITE DWARFS and NEUTRON STARS

• Luminosity varitions due to radial and
  non-radial pulsations
• Oscillations time-scale white dwarfs ?
  1001000 ms
• 
  neutron stars ? 100 ?s

superposition of vibrational modes light output
variations asteroseismological evidence about
the interiors of the star
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4-6 APRIL

• Object RA Dec Type ltmgt ?mpuls Period(s) (sec)
• HE 12580123 13 01 110.5 01 07 39.7 DAV 16.26
  (V) 0.18 (V) 529 - 1092
• IU Vir 14 03 57.2 -15 01 10 DAV 15.67 (B) 0.30
  (B) 399, 610, 724, 937
• TY CrB 16 01 21.2 36 48 34.3 DAV 14.36 (V) 0.15
  (V) 833, complex
• V470 Lyr 18 57 30.2 33 57
  25.9 DAV 14.62 (V) 0.06 (V) 259, 292, 557, 739
• PT Vul 19 52 28 25 09 24 DAV 15.12 (V) 0.05
  (V) 256
• Object RA Dec Type ltmgt ?mpuls Period(s) (sec)
• ZZ Cet 01 36 13.6 -11 20 32.2 DAV 14.16 (V) 0.01
  (V) 213, 274
• GD 1400 01 47 21.8 -21
  56 51 DAV 15.4 (V) 0.24 (V) 462 - 823
• V411 Tau 04 18 56.5 27 17 51.4 DAV 15.20
  (V) 0.28 (V) 494, 625, 746

8-12 OCTOBER
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22-27 DECEMBER

• Object RA Dec Type ltmgt ?mpuls Period(s)
  (sec)
• ZZ Cet 01 36 13.6 -11 20 32.2 DAV 14.16
  (V) 0.01 (V) 213, 274
• V411 Tau 04 18 56.5 27 17 51.4 DAV 15.20
  (V) 0.28 (V) 494, 625, 746
• V468 Per 04 20 18 36 16 36 DAV 15.59
  (V) 0.22 (V) 910, 1024
• V1396 Ori 05 10 13.9 04 38 44 DAV 15.36
  (V) 0.2 (V) 355, 445, 560
• VW Lyn 09 01 48.7 36 07 07.7 DAV 14.55
  (V) 0.07 (V) 350, 481, 592
• RY LMi 09 24 16 35 16 54 DAV 15.50
  (V) 0.06 (V) 215, 271, 304
• SW LMi 09 57 50 33 59 42 DBV 17.2
  (B) 0.30 (B) 650, complex
• DAV ZZ Cet WD, DBV V777 Her WD, DOV GW Vir

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FLARE STARS
FLARE STARS variable star which can undergo
unpredictable increases
in brightness for a few minutes
4-6 APRIL

• Object RA(J2000) Dec(J2000) ltmgt TSp
• FL Vir 12 33 26.5 09 01 01 12.50
  (V) dM5.5e/M7
• GJ 643 16 55 25.23 -08 19 21.3 11.70
  (V) dM3.5
• V1054 Oph 16 55 28.76 -08 20 10.8 9.04
  (V) dM3e
• VB8 (Gl644C) 16 55 35.74 -08 23 36.0 16.70
  (V) dM7
• Object RA(J2000) Dec(J2000) ltmgt TSp
• V1005 Ori 04 59 35.1 01 47 09 10.05 (V) M1Ve
• YZ CMi 07 44 43 03 33.7 11.12 (V) dM4.5

8-12, 22-27 OTTOBRE
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PLANETARY NEBULAE

• PLANETARY NEBULAE astrophysical
  laser emissions

NGC 7027
RA Dec ltmgt
21 07 01.6 42 14 10.2 8.8 (V)
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STARS WITH TRANSITING EXOPLANETS

• observation of planetary transit
• (for a large time span!)
• accurate evaluation of the transit starting time
• observation of TTVs (Transit Timing Variations)
• detection of other exoplanets orbiting around
• the same parent star

high time resolution
detection of companion planets with
small masses large mutual distances
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4-6 APRIL
Object RA Dec ltmgt Porb (day) Mass (MJ) XO-1 16
02 12 28 10 11 11.3 (V) 3.941534 0.9 HD147506
16 20 36 41 02 53 8.71 (V) 5.63341 8.17 HD14
9026 16 30 29 38 20 50 8.15 (V) 2.8766 0.36 TrES-
3 17 52 07 37 32 46 12.4 (V) 1.30619 1.92 TrES-1
19 04 09 36 37 57 11.79 (V) 3.0300737 0.61 TrES-2
19 07 14 49 18 59 11.41 (V) 2.47063 1.98
8-12 OCTOBER
Object RA Dec ltmgt Porb (day) Mass (MJ) WASP-1 00
20 40 31 59 24 11.79 (V) 2.51997 0.89 XO-2 07 48
07 50 13 33 11.18 (V) 2.615838 0.57
22-27 DECEMBER
Object RA Dec ltmgt Porb (day) Mass (MJ) XO-2 07 48
07 50 13 33 11.18 (V) 2.615838 0.57