scholarly journals Shaping proto-planetary nebulae by binary systems

2011 ◽  
Vol 7 (S283) ◽  
pp. 103-106 ◽  
Author(s):  
A. Riera ◽  
P. F. Velázquez ◽  
W. Steffen ◽  
A. C. Raga ◽  
J. Cantó
Keyword(s):  
Binary System ◽  
Accretion Disk ◽  
Binary Systems ◽  
Orbital Motion ◽  
Planetary Nebulae ◽  
Time Dependent ◽  
Ejection Velocity ◽  
Hydrodynamic Simulations ◽  
Secondary Star ◽  
Hydrodynamical Simulations

AbstractWe present the results of 3D hydrodynamic simulations aimed to explore the binary scenario for shaping bipolar, point- and mirror-symmetric proto-Planetary Nebulae. We consider a jet launched by the secondary star of a binary system, located at the center of the PPN, which propagates within a circumstellar medium swept previously up by the wind of the giant companion. As a result of the presence of the companion star, the accretion disk around the jet source is likely to precess. We have carried out 3D hydrodynamical simulations with the YGUAZÚ-A code including the combination of an orbital motion plus a precession. Our results show that to produce a multipolar nebula, it is necessary to have a precessing jet in a binary system with a time-dependent ejection velocity.

scholarly journals Shaping planetary nebulae with jets in inclined triple stellar systems

2016 ◽  
Vol 12 (S323) ◽  
pp. 227-230
Author(s):  
Muhammad Akashi ◽  
Noam Soker
Keyword(s):  
Binary System ◽  
Accretion Disk ◽  
Planetary Nebula ◽  
Initial Conditions ◽  
Three Dimensional ◽  
Orbital Plane ◽  
Planetary Nebulae ◽  
Asymptotic Giant Branch ◽  
Stellar Systems ◽  
Hydrodynamical Simulations

AbstractWe conduct three-dimensional hydrodynamical simulations of two opposite jets launched obliquely to the orbital plane around an asymptotic giant branch (AGB) star and within its dense wind, and demonstrate the formation of a ‘messy’ planetary nebula (PN), namely, a PN lacking any type of symmetry (highly irregular). In building the initial conditions we assume that a tight binary system orbits the AGB star, and that the orbital plane of the tight binary system is inclined to the orbital plane of binary system and the AGB star. We further assume that the accreted mass onto the tight binary system forms an accretion disk around one of the stars, and that the plane of the disk is in between the two orbital planes. The highly asymmetrical lobes that we obtain support the notion that messy PNe might be shaped by triple stellar systems.

scholarly journals Wiggling Structures Along the NGC 1333 IRAS 2A Outflow

2012 ◽  
Vol 8 (S292) ◽  
pp. 60-60
Author(s):  
Cheng-Hung Tsai ◽  
Huei-Ru Chen ◽  
Chin-Fei Lee ◽  
Naomi Hirano ◽  
Hsien Shang
Keyword(s):  
Binary System ◽  
Accretion Disk ◽  
Mirror Symmetry ◽  
Large Scale ◽  
Angular Resolution ◽  
Orbital Motion ◽  
Lateral Displacement ◽  
Binary Separation ◽  
Bipolar Outflow ◽  
Small Separation

AbstractWiggling structures in a bipolar outflow may be attributed to orbital motion of a binary system or precession of an accretion disk perturbed by a companion. The shocked knots along the outflow axis display a morphology with either mirror symmetry due to the orbital motion or point symmetry resulted from disk precession. Using the Submillimeter Array (SMA), our CO (2-1) and SiO (5-4) observations show wiggling structures in the collimated bipolar outflow driven by the NGC 1333 IRAS 2A Class 0 protostar (d ~ 200 pc). By fitting the peak positions of emission knots, we can examine the lateral displacement of the molecular jet to constrain parameters of the unresolved binary system, such as the binary separation and total binary mass. With an angular resolution of ~3″, we have determined the knot positions in SiO (5–4)(Fig. 1) and CO (2–1). As a first attempt, we consider the scenario of orbital motion in a binary system and estimate a total binary mass of ~ 1M⊙ and a binary separation of roughly ~ 20 AU, corresponding to ~ 0.1″. Such a small separation makes it challenging to resolve this hypothesized proto-binary system, which is thought to be responsible for the large-scale quadrupolar outflow nearly perpendicular with each other in CO (1–0).

scholarly journals Light curve analysis of the eclipsing binary system V781 Tau

2021 ◽  
Vol 2145 (1) ◽  
pp. 012005
Author(s):  
N Lamlert ◽  
W Maithong
Keyword(s):  
Binary System ◽  
Light Curve ◽  
Orbital Period ◽  
Binary Systems ◽  
Curve Analysis ◽  
Photometric System ◽  
Light Curve Analysis ◽  
Eclipsing Binary ◽  
The Public ◽  
Secondary Star

Abstract V781 Tau is one of W UMa eclipsing binary systems whose orbital period is 0.34 days. The 0.7-meter telescope with CCD photometric system in B and V filters was conducted at the Regional Observatory for the Public, Chachoengsao, Thailand during December 2018, UT. The Wilson-Devinney Technique was used for calculating the physical properties of V781 Tau. The results showed the inclination of their orbital is 66.140°±0.14. The effective temperature of the primary and secondary star is 6,060 and 5,881 K, respectively and the degree of contact is 4.38 %

scholarly journals Multipolar young planetary nebulae modelled as a precessing and orbiting jet with time-dependent ejection velocity

2011 ◽  
Vol 419 (4) ◽  
pp. 3529-3536 ◽  
Author(s):  
Pablo F. Velázquez ◽  
Alejandro C. Raga ◽  
Angels Riera ◽  
Wolfgang Steffen ◽  
Alejandro Esquivel ◽  
...  
Keyword(s):  
Planetary Nebulae ◽  
Time Dependent ◽  
Ejection Velocity

scholarly journals Rotating Progenitors of the Wolf-Rayet Binaries HD186943 and HD90657

2004 ◽  
Vol 194 ◽  
pp. 231-231
Author(s):  
Jelena Petrovic ◽  
Norbert Langer
Keyword(s):  
Mass Transfer ◽  
Binary System ◽  
Mass Loss ◽  
Binary Systems ◽  
Secondary Star ◽  
Break Up ◽  
Orbital Periods ◽  
Significant Mass Loss ◽  
Significant Mass

We present rotating progenitor models for the WR+O binary systems HD186943 and HD90657 (van der Hucht, 2001) calculated with the evolutionary code described by Wellstein (2001). Due to rotation, the effective accretion onto the secondary star is reduced as it is spun-up close to its break-up velocity and thereby undergoes strong mass loss. We investigate the progenitor evolution of the two observed WR+O binary systems through stable mass transfer. We conclude that these systems evolved through Case A mass transfer as they have short orbital periods now (8…10 days), and the progenitor systems must have started with a shorter or equal period. We show that there has to be a significant mass loss from the binary system to produce WR+O systems similar to the observed ones. The accretion efficiency of the secondary star in our rotating models is ~10%. We compare properties of the observed and modelled systems in Table 1.

scholarly journals X-ray and UV emission of the ultrashort-period, low-mass eclipsing binary system BX Trianguli

2018 ◽  
Vol 619 ◽  
pp. A138
Author(s):  
V. Perdelwitz ◽  
S. Czesla ◽  
J. Robrade ◽  
T. Pribulla ◽  
J. H. M. M. Schmitt
Keyword(s):  
Binary System ◽  
Light Curve ◽  
Binary Systems ◽  
Uv Light ◽  
Close Binary ◽  
Eclipsing Binary ◽  
X Ray ◽  
Uv Emission ◽  
Low Mass ◽  
Orbital Modulation

Context.Close binary systems provide an excellent tool for determining stellar parameters such as radii and masses with a high degree of precision. Due to the high rotational velocities, most of these systems exhibit strong signs of magnetic activity, postulated to be the underlying reason for radius inflation in many of the components. Aims.We extend the sample of low-mass binary systems with well-known X-ray properties. Methods.We analyze data from a singular XMM-Newton pointing of the close, low-mass eclipsing binary system BX Tri. The UV light curve was modeled with the eclipsing binary modeling tool PHOEBE and data acquired with the EPIC cameras was analyzed to search for hints of orbital modulation. Results.We find clear evidence of orbital modulation in the UV light curve and show that PHOEBE is fully capable of modeling data within this wavelength range. Comparison to a theoretical flux prediction based on PHOENIX models shows that the majority of UV emission is of photospheric origin. While the X-ray light curve does exhibit strong variations, the signal-to-noise ratio of the observation is insufficient for a clear detection of signs of orbital modulation. There is evidence of a Neupert-like correlation between UV and X-ray data.

Phase transition-induced changes in the Raman properties of DMSO/benzene binary systems

2021 ◽  
Vol 23 (15) ◽  
pp. 9211-9217
Author(s):  
Guannan Qu ◽  
Rasheed Bilal ◽  
Minsi Xin ◽  
Zhong Lv ◽  
Guangyong Jin ◽  
...  
Keyword(s):  
Phase Transition ◽  
Hydrogen Bond ◽  
Binary System ◽  
Binary Systems ◽  
Induced Changes

Hydrogen bond generated between DMSO and benzene binary system induced changes in the Raman properties during phase transition.

scholarly journals The effect of photoionizing feedback on the shaping of hierarchically-forming stellar clusters

2020 ◽  
Vol 499 (1) ◽  
pp. 668-680
Author(s):  
Alejandro González-Samaniego ◽  
Enrique Vazquez-Semadeni
Keyword(s):  
Star Formation ◽  
Early Stage ◽  
Stellar Clusters ◽  
Low Mass Stars ◽  
Transfer Scheme ◽  
Star Forming ◽  
Secondary Star ◽  
Low Mass ◽  
Hydrodynamical Simulations ◽  
Formation Efficiency

ABSTRACT We use two hydrodynamical simulations (with and without photoionizing feedback) of the self-consistent evolution of molecular clouds (MCs) undergoing global hierarchical collapse (GHC), to study the effect of the feedback on the structural and kinematic properties of the gas and the stellar clusters formed in the clouds. During this early stage, the evolution of the two simulations is very similar (implying that the feedback from low-mass stars does not affect the cloud-scale evolution significantly) and the star-forming region accretes faster than it can convert gas into stars, causing the instantaneous measured star formation efficiency (SFE) to remain low even in the absence of significant feedback. Afterwards, the ionizing feedback first destroys the filamentary supply to star-forming hubs and ultimately removes the gas from it, thus first reducing the star formation (SF) and finally halting it. The ionizing feedback also affects the initial kinematics and spatial distribution of the forming stars because the gas being dispersed continues to form stars, which inherit its motion. In the non-feedback simulation, the groups remain highly compact and do not mix, while in the run with feedback, the gas dispersal causes each group to expand, and the cluster expansion thus consists of the combined expansion of the groups. Most secondary star-forming sites around the main hub are also present in the non-feedback run, implying a primordial rather than triggered nature. We do find one example of a peripheral star-forming site that appears only in the feedback run, thus having a triggered origin. However, this appears to be the exception rather than the rule, although this may be an artefact of our simplified radiative transfer scheme.

scholarly journals Reconstruction of an Accretion Disk Image in AU Mon from CoRoT Photometry

2011 ◽  
Vol 7 (S282) ◽  
pp. 63-64
Author(s):  
P. Mimica ◽  
K. Pavlovski
Keyword(s):  
Binary System ◽  
Accretion Disk ◽  
Hot Spots ◽  
Disk Surface ◽  
Precise Location ◽  
Active Mass ◽  
Disk Structure ◽  
Surface Time ◽  
Photometric Measurements ◽  
Disk Image

AbstractThe long-period binary system AU Mon was photometrically observed on-board the CoRoT satellite in a continuous run of almost 60 days long which has covered almost 5 complete cycles. Unprecedented sub milimag precision of CoRoT photometry reveals all complexity of its light variations in this, still active mass-transfer binary system. We present images of an accretion disk reconstructed by eclipse mapping, and an optimization of intensity distribution along disk surface. Time resolution and accurate CoRoT photometric measurements allow precise location of spatial distribution of ‘hot’ spots on the disk, and tracing temporal changes in their activity. Clumpy disk structure is similar to those we detected early for another W Serpentis binary W Cru (Pavlovski, Burki & Mimica, 2006, A&A, 454, 855).

Sign in / Sign up

Export Citation Format

Share Document