ACCRETION DISK IN THE MASSIVE CLOSE BINARY STARS G O J K O J U - - PowerPoint PPT Presentation

▶
accretion disk in the massive close binary stars
SMART_READER_LITE
LIVE PREVIEW

ACCRETION DISK IN THE MASSIVE CLOSE BINARY STARS G O J K O J U - - PowerPoint PPT Presentation

Jun 03, 2023 6 likes •466 views

ACCRETION DISK IN THE MASSIVE CLOSE BINARY STARS G O J K O J U R A E V I S T E L L A R P H Y S I C S G R O U P ( O N 1 7 6 0 0 4 ) A S T R O N O M I C A L O B S E R V A T O R Y B E L G R A D E E - M A I L : G D J U R A S E V I

slide-1
SLIDE 1

G O J K O ĐJ U R A Š E V I Ć

S T E L L A R P H Y S I C S G R O U P ( O N 1 7 6 0 0 4 ) A S T R O N O M I C A L O B S E R V A T O R Y B E L G R A D E E - M A I L : G D J U R A S E V I C @ A O B . R S

ACCRETION DISK IN THE MASSIVE CLOSE BINARY STARS

slide-2
SLIDE 2

About us

  • G. Đurašević (founder), A. Cséki

(adm inistrator), S. Jankov, O. Atanacković, I. Vince, V. Čadež,

  • B. Arbutina, O. Vince, I. Milić, M.

Jurković, O. Latković, J. Petrović, S. Lazarević

People in the group

  • Close binary stars m odeling and

evolution

  • Num erical m ethods in radiation

transfer; transfer of polarized radiation

  • Stellar oscillations in single and

binary stars; stellar rotation and the Be phenom enon Areas of interest

slide-3
SLIDE 3

About this talk

 Binary stars as the main origin of

the fundamental stellar parameters in astrophysics

 We use our own modeling tools  Recent topics

Modeling of the massive CBS

 Double-periodic variables  Evolution status of these systems

 Future research

 Innovative optim ization techniques

slide-4
SLIDE 4

Why are we still interested in binary stars?

Multiplicity is everywhere

Star form ation Population synthesis

Growing sample, better statistics

Space telescopes Long-term surveys Autom ated analysis

New phenomena

Accretion disk in the m assive CBS Double-periodic variables

slide-5
SLIDE 5

“Solving” individual objects

Observations

  • RV curves
  • Light curves

Detailed modeling Orbital and stellar parameters

Seasonal light curves of V455 Cyg in the year 2002. From Djurasevic et al., 2012, MNRAS, 420, 308

slide-6
SLIDE 6

“Solving” individual objects

Observations

  • RV curves
  • Light curves

Detailed modeling Orbital and stellar parameters

Radial velocity curves of V455 Cyg. From Djurasevic et al., 2012, MNRAS, 420, 308

slide-7
SLIDE 7

“Solving” individual objects

Observations

  • RV curves
  • Light curves

Detailed modeling Orbital and stellar parameters

Model of V455 Cyg. From Djurasevic et al., 2012, MNRAS, 420, 308

slide-8
SLIDE 8

We develop and maintain

  • ur own modeling tools

Binary system modeling software created by

  • G. Đurašević
  • Based on

Roche geometry

  • In constant

development

  • Accretion disks
  • Extremely fast

Infinity

  • Reimagined geometrical

representation

  • Eccentric systems
  • Simultaneous fitting of

LC and RVC

  • Stellar oscillations
  • And more…
  • …

at the cost of speed.

Future improvements

  • Circumstellar structures
  • Circumbinary

structures

  • Synthetic spectra
  • Synthetic polarized light

curves

slide-9
SLIDE 9

S H OR T H IS TOR Y OF TH E M OD ELIN G TH ES E VAR IAB LES OVER -CON TACT OR TH E S YS TEM S W ITH ACCR ETION D IS K ?

High Mass Binaries: Some unresolved problems concerning the light curve modeling

slide-10
SLIDE 10
slide-11
SLIDE 11

The Astronomical Journal, 136:767– 772, 2008 August ACCRETION DISK IN THE MASSIVE BINARY RY SCUTI

  • G. Djurašević, I. Vince,
  • O. Atanacković1
slide-12
SLIDE 12
slide-13
SLIDE 13
slide-14
SLIDE 14
slide-15
SLIDE 15
slide-16
SLIDE 16

The temperature distribution along disk radius

slide-17
SLIDE 17
slide-18
SLIDE 18

AU Mon

Ултра-прецизна фотометрија са сателитског телескопа CoRoT

slide-19
SLIDE 19

AU Mon

Desmet et al. 2010, MNRAS, 401, 418

slide-20
SLIDE 20

AU Mon

Đurašević, Latković, Vince & Čeki 2010, MNRAS, 409, 329

slide-21
SLIDE 21

AU Mon

Đurašević, Latković, Vince & Čeki 2010, MNRAS, 409, 329

slide-22
SLIDE 22

Discovery of the Double-periodic variables

slide-23
SLIDE 23

Double-periodic variables

Two photometric periodicities Semidetached binaries in midst of mass transfer Census Nature of long cycle ? Disentangled light curve of V495 Cen. Orbital Period is P~33d and long cycle is LP~1283d. From Mennickent & Rosales, 2014, IBVS 6116,1

slide-24
SLIDE 24

Double-periodic variables

Two photometric periodicities Semidetached binaries in midst of mass transfer Census Nature of long cycle ? Orbital periods and long cycles for the entire DPV sample. From Mennickent, 2017, Ser AJ 194, 1

slide-25
SLIDE 25

Double-periodic variables

Two photometric periodicities

  • Intermediate to high mass
  • Low mass ratio
  • Accretion disk
  • Hot spot + winds/ jets

Semidetached binaries in midst of mass transfer Census Nature of long cycle

Morphology of DPV HD 170582. From Mennickent, Djurasevic et al., 2015, MNRAS 448, 1137

slide-26
SLIDE 26

Double-periodic variables

Two photometric periodicities Semidetached binaries in midst of mass transfer Census Nature of long cycle ... ? Com parison of galactic Algols and DPVs on HR and ML diagram . From Mennickent, 2017, SerAJ 194, 1

slide-27
SLIDE 27

Double-periodic variables

Two photometric periodicities Semidetached binaries in midst of mass transfer Census

  • Magnetically active donor
  • Applegate mechanism
  • Variable oblateness
  • Variable accretion rate
  • ? ..........

Nature of long cycle Ratio of long to short cycle vs. short cycle from dynam o m odel. From Schleicher & Mennickent, 2017, A&A, 602, A109

slide-28
SLIDE 28
slide-29
SLIDE 29
slide-30
SLIDE 30
slide-31
SLIDE 31
slide-32
SLIDE 32
slide-33
SLIDE 33
slide-34
SLIDE 34
slide-35
SLIDE 35
slide-36
SLIDE 36
slide-37
SLIDE 37
slide-38
SLIDE 38
slide-39
SLIDE 39
slide-40
SLIDE 40
slide-41
SLIDE 41
slide-42
SLIDE 42
slide-43
SLIDE 43
slide-44
SLIDE 44
slide-45
SLIDE 45
slide-46
SLIDE 46