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AQUEYE: SCIENTIFIC TARGETS. 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
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AQUEYE:SCIENTIFIC TARGETS Anna Sponselli
Aqueye: ultrafastphotometer 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 Anna Sponselli
PULSAR Formation by a supernova explosion Neutron star extremely high density extremely high rotational velocity (periods range from 1.5 ms to 8.5 s ) intense magnetic field (typically in the range of 10^8 - 10^12 gauss ) Anna Sponselli
Pulsars are highly magnetized rotating neutron stars • Accelerated charged particles emissions in radio, visible, x-ray and -ray domains Anna Sponselli
pulsed nature • Lighthouse effect • extraordinarily rapid and stable rotation very regular rotation period (the regularity of pulsation is as precise as an atomic clock) pulsars as useful instrument for Aqueye’s calibration Anna Sponselli
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’’
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 Anna Sponselli
2) Intermediate- Polars (DQ Herculis stars) 3) Polars (AM herculis stars) Anna Sponselli
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)
WHY IS FLICKERING IMPORTANT? 1) it’s a fundamental signature of accretion processes 2) it represents a significant fraction of the total luminosity of the source OPEN QUESTIONS : 1) what’s 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 understanding the physics occurring at much shorter time-scales HIGH SPEED PHOTOMETRY
4-6 APRIL • Object RA(J2000) Dec(J2000) Type <m> Δmorb 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 <m> Δmorb Pspin (s) Porb (h) • WW Cet 00 11 24.8 -11 28 42.7 DN 13.9 (V) 2.2 (V) 591 4.219 • V709 Cas 00 28 48.9 +59 17 21.8 IP 14.1 (V) 0.5 (V) 312.75 5.340 • 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 - P = polar, IP = intermediate polar, N = nova, NL = nova-like, DN = dwarf nova 8-12 OCTOBER Anna Sponselli
22-27 OCTOBER • Object RA(J2000) Dec(J2000) Type <m> Δmorb 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 Anna Sponselli
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? Anna Sponselli
PULSATING WHITE DWARFS and NEUTRON STARS • Luminosity varitions due to radial and non-radial pulsations: • Oscillations time-scale: white dwarfs 100–1000 ms neutron stars 100 s superposition of vibrational modes light output variations asteroseismological evidence about the interiors of the star Anna Sponselli
4-6 APRIL • Object RA Dec Type <m> Δmpuls Period(s) (sec) • HE 1258+0123 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 <m> Δmpuls 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 • 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 DAV = ZZ Cet WD, DBV = V777 Her WD, DOV = GW Vir 8-12 OCTOBER Anna Sponselli
22-27 DECEMBER • Object RA Dec Type <m> Δmpuls 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 Anna Sponselli
FLARE STARS FLARE STARS = variable star which can undergo unpredictable increases in brightness for a few minutes • Object RA(J2000) Dec(J2000) <m> 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) <m> 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° 4-6 APRIL 8-12, 22-27 OTTOBRE Anna Sponselli
PLANETARY NEBULAE PLANETARY NEBULAE astrophysical laser emissions NGC 7027 : RA Dec <m> 21 07 01.6 +42 14 10.2 8.8 (V) Anna Sponselli
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 Anna Sponselli
4-6 APRIL Object RA Dec <m> 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 HD149026 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 <m> 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 <m> Porb (day) Mass (MJ) XO-2 07 48 07 +50 13 33 11.18 (V) 2.615838 0.57 Anna Sponselli