arXiv subjects

Guoliang Lu

Publications and source records attributed to Guoliang Lu.

14 recordsLinked to original sources

arXiv2026

SN 2021pfs: A Type Ia Supernova Likely Affected by Progenitor Metallicity, as Revealed by Comparison with Its Twin Counterpart

We present extensive photometric and spectroscopic observations of the normal type Ia supernovae (SNe Ia) 2021pfs, which occurred in the Seyfert 2 galaxy NGC 5427 at a redshift 0.009. SN 2021pfs reached an absolute \textit{B}-band peak magnitude of $M_{\rm max}(B)=$-19.28 $\pm$ 0.40 mag. The mag and a post-peak decline rate of $\Delta m_{15}(B)=$1.13 $\pm$ 0.06 mag. The observed properties of this nearby SN Ia closely resemble those of SN 2011fe, including the main optical spectroscopic features and photometric evolution. Despite their similar decline rates, SN 2021pfs rose more rapidly in the $U$ band but more slowly in the $r$ and $i$ bands compared to SN 2011fe in very early phases. This photometric difference, particularly at short wavelengths, can introduce a systematic uncertainty of up to $\sim$12% in distance estimates. Analysis of the host galaxy's local and global environment shows an environment consistent with producing a higher-metallicity progenitor for SN 2021pfs than that of SN 2011fe.This higher progenitor metallicity may explain the observed photometric discrepancy and the resulting distance between SN 2021pfs and SN 2011fe, though a larger sample of such "twin" SNe Ia is needed to confirm this trend and assess its impact on cosmological measurements.

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arXiv2025

Orbital Parameters of 665 Double-lined Spectroscopic Binaries in the LAMOST Medium-Resolution Survey

The period, mass ratio, eccentricity, and other orbital parameters are fundamental for investigating binary star evolution. However, the number of binaries with known orbital parameters remains limited. Utilizing the LAMOST-MRS survey, we derived orbital solutions for 665 SB2 binaries by fitting the radial velocities of 1119 SB2 systems with at least six observations, employing a modified version of Thejoker optimized for SB2 binaries. To ensure the reliability of the results, four selection criteria were applied: reduced chi-square, normalized mean absolute error, maximum phase gap, and RV distribution metric. After applying these criteria, 665 reliable orbits were retained. Comparison with Kepler, TESS, and ZTF light curve data shows excellent agreement, with discrepancies in some cases attributed to shorter pulsation periods observed in light curves. Additionally, good consistency is found between our periods and those of SB1 systems in Gaia data. These orbital solutions contribute to understanding binary star evolution and the statistical properties of binary populations.

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arXiv2023

The effects of rotation, metallicity and magnetic field on the islands of failed supernovae

Failed supernovae (FSN) are a possible channel for the formation of heavy stellar-mass black holes ($M_{ BH}>\sim 30$ M$_\odot$). However, the effects of metallicity, rotation and magnetic field on the islands of explodabilty of massive stars are not clear. Here, we simulate the stellar structure and evolution in the mass range between 6 and 55 $M_{\odot}$ with different initial rotational velocities, metallicities, and magnetic fields from zero-age main sequence (ZAMS) to pre-collapse. We find that the rapid rotating stars can remain lower $\rm ^{12}C$ mass fraction at the time of C ignition, which allows the transition, from convective carbon burning to radiative burning, to occur at lower $M_{\rm ZAMS}$ than those from stars without rotation. However, the rapid rotation is unfavorable for FSN occurring but is conducive to long gamma-ray bursts (lGRBs) because it results in the specific angular momentum in the CO core is greater than the last stable orbit at core collapse. The increasing metallicity does not affect FSN islands, but high metallicity inhibits rotational mixing and is unfavorable for producing lGRBs. A magnetic field can constrain the mass-loss rate even for rapid rotating stars, resulting in higher mass at pre-collapse. The magnetic braking triggered by the magnetic field can reduce the rotation velocity for high-metallicity models, which decreases the specific angular momentum in the CO core and is favorable for FSN occurring. We suggest that the heavy-mass black holes detected by LIGO may originate from rapidly rotating massive stars with strong magnetic fields, rather than those with very low metallicity.

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arXiv2018

A Study of Wolf-Rayet stars Formed via Chemically Homogeneous Evolution

Using the stellar evolution code---Modules for Experiments in Stellar Astrophysics (MESA), we investigate the evolution of massive stars with different rotational velocities and metallicities towards Wolf-Rayet stars. In our simulations, the initial rotating velocities are taken as 0, 250, 500 and 650 km s$^{-1}$, and the metallicities equal to 0.02, 0.014, 0.008, 0.006, 0.004 and 0.002. We show our rapid rotation models in the HR diagram compared with the observations. We find that the rotational mixing is less efficient at high metallicity, and these stars become Wolf-Rayet (WR) stars when the helium in their center is ignited. However, rapid rotating massive stars at low metallicity can easily evolve into WR stars due to the rotation resulted in chemically homogeneous evolution. This can explain the origin of single WR stars in galaxy at low metallicity. In our models, the observed SMC WR stars are consistent with the single-star evolution models. However at higher metallicities our single-star evolution models can only explain the luminous, hydrogen-rich WN stars and O stars (which are classified as WR stars previously).

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arXiv2017

Effects of the core-collapse supernova ejecta impact on a rapidly rotating massive companion star

We investigate the effects of the core-collapse supernova ejecta on a rapidly rotating and massive companion star. We show that the stripped mass raises by twice when compare with a massive but non-rotating companion star. In close binaries with orbital periods of about 1 day, the stripped masses reach up to $\sim 1 M_\odot$. By simulating the evolutions of the rotational velocities of the massive companion stars based on different stripped masses, we find that the rotational velocity decreases greatly for stripped mass that is higher than about $1 M_\odot$. Of all the known high mass X-ray binaries (HMXBs), Cygnus X-3 and 1WGA J0648.024418 have the shortest orbital periods of 0.2 and 1.55 days, respectively. The optical counterpart of the former is a Wolf-Rayet star, whereas it is a hot subdwarf for the latter. Applying our model to the two HMXBs, we suggest that the hydrogen-rich envelopes of their optical counterparts may have been stripped by CCSN ejecta.

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arXiv2016

The diamagnetic phase transition in Magnetars

Neutron stars are ideal astrophysical laboratories for testing theories of the de Haas-van Alphen (dHvA) effect and diamagnetic phase transition which is associated with magnetic domain formation. The "magnetic interaction" between delocalized magnetic moments of electrons (the Shoenberg effect), can result in an effect of the diamagnetic phase transition into domains of alternating magnetization (Condon's domains). Associated with the domain formation are prominent magnetic field oscillation and anisotropic magnetic stress which may be large enough to fracture the crust of magnetar with a super-strong field. Even if the fracture is impossible as in "low-field" magnetar, the depinning phase transition of domain wall motion driven by low field rate (mainly due to the Hall effect) in the randomly perturbed crust can result in a catastrophically variation of magnetic field. This intermittent motion, similar to the avalanche process, makes the Hall effect be dissipative. These qualitative consequences about magnetized electron gas are consistent with observations of magnetar emission, and especially the threshold critical dynamics of driven domain wall can partially overcome the difficulties of "low-field" magnetar bursts and the heating mechanism of transient, or "outbursting" magnetar.

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arXiv2016

The Contribution of Chemical Abundances in Nova Ejecta to the Interstellar Medium

According to the nova model from \citet{Yaron2005} and \citet{Jose1998} and using Monte Carlo simulation method, we investigate the contribution of chemical abundances in nova ejecta to the interstellar medium (ISM) of the Galaxy. We find that the ejected mass by classical novae (CNe) is about $2.7\times10^{-3}$ $ \rm M_\odot\ {\rm yr^{-1}}$. In the nova ejecta, the isotopic ratios of C, N and O, that is, $^{13}$C/$^{12}$C, $^{15}$N/$^{14}$N and $^{17}$O/$^{16}$O, are higher about one order of magnitude than those in red giants. We estimate that about 10$\%$, 5$\%$ and 20$\%$ of $^{13}$C, $^{15}$N and $^{17}$O in the ISM of the Galaxy come from nova ejecta, respectively. However, the chemical abundances of C, N and O calculated by our model can not cover all of observational values. This means that there is still a long way to go for understanding novae.

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arXiv2015

Population Synthesis of Millisecond X-ray Pulsars

As the evolutionary link between the radio millisecond pulsars (MSPs) and the low mass X-ray binaries or intermediate mass X-ray binaries, the millisecond X-ray pulsars (MSXPs) are important objects in testing theories of pulsar formation and evolution. In general, neutron stars in MSXPs can form via core collapse supernova (CC channel) of massive stars or accretion induced collapse (AIC channel) of an accreting ONeMg WD whose mass reaches the Chandrasekhar limit. Here, in addition to CC and AIC channels we also consider another channel, i.e., evolution induced collapse (EIC channel) of a helium star with mass between $1.4$ and $2.5 M_{\odot}$. Using a population synthesis code, we have studied MSXPs arising from three different evolutionary channels. We find that the Galactic birthrates of transient MSXPs and persistent MSXPs are about 0.7---$1.4\times 10^{-4}$ yr$^{-1}$. Our population synthesis calculations have shown that about 50\%---90\% of the MSXPs have undergone CC channel, about 10\%---40\% of them have undergone EIC channel, and the MSXPs via AIC channel are the least.

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arXiv2013

Origin of Dust around V1309 Sco

The origin of dust grains in the interstellar medium is still open problem. \cite{Nicholls2013} found the presence of a significant amount of dust around V1309 Sco which maybe originate from the merger of a contact binary. We investigate the origin of dust around V1309 Sco, and suggest that these dust grains are efficiently produced in the binary-merger ejecta. By means of \emph{AGBDUST} code, we estimate that $\sim 5.2\times10^{-4} M_\odot$ of dust grains are produced, and their radii are $\sim 10^{-5}$ cm. These dust grains mainly are composed of silicate and iron grains. Because the mass of the binary-merger ejecta is very small, the contribution of dust produced by binary-merger ejecta to the overall dust production in the interstellar medium is negligible. However, it is the most important that the discovery of a significant amount of dust around V1309 Sco offers a direct support for the idea---common-envelope ejecta provides an ideal environment for dust formation and growth. Therefore, we confirm that common-envelope ejecta can be important source of cosmic dust.

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arXiv2013

Dust Formation in the Ejecta of Common Envelope Systems

The material that is ejected in a common-envelope (CE) phase in a close binary system provides an ideal environment for dust formation. By constructing a simple toy model to describe the evolution of the density and the temperature of CE ejecta and using the \emph{AGBDUST} code to model dust formation, we show that dust can form efficiently in this environment. The actual dust masses produced in the CE ejecta depend strongly on their temperature and density evolution. We estimate the total dust masses produced by CE evolution by means of a population synthesis code and show that, compared to dust production in AGB stars, the dust produced in CE ejecta may be quite significant and could even dominate under certain circumstances.

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arXiv2011

Gamma-ray sources like V407 Cygni in Symbiotic Stars

Using a simple accelerating model and an assumption that $γ$-rays originate from $p-p$ collisions for a $π^0$ model, we investigate $γ$-ray sources like V407 Cygni in symbiotic stars. The upper limit of their occurrence rate in the Galaxy is between 0.5 and 5 yr$^{-1}$, indicating that they may be an important source of the high-energy $γ$-rays. The maximum energies of the accelerated protons mainly distribute around $10^{11}$ eV, and barely reach $10^{15}$ eV. The novae occurring in D-type SSs with ONe WDs and long orbital periods are good candidates for $γ$-ray sources. Due to a short orbital period which results in a short acceleration duration, the nova occurring in symbiotic star RS Oph can not produce the $γ$-ray emission like that in V407 Cygni.

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arXiv2009

Soft and Supersoft X-ray Sources in Symbiotic Stars

Assuming that soft X-ray sources in symbiotic stars result from strong thermonuclear runaways, and supersoft X-ray sources from weak thermonuclear runaways or steady hydrogen burning symbiotic stars, we investigate the Galactic soft and supersoft X-ray sources in symbiotic stars by means of population synthesis. The Galactic occurrence rates of soft X-ray sources and supersoft X-ray sources are from $\sim$ 2 to 20 $\rm yr^{-1}$, and $\sim$ 2 to 17 $\rm yr^{-1}$, respectively. The numbers of X-ray sources in symbiotic stars range from 2390 to 6120. We simulate the distribution of X-ray sources over orbital periods, masses and mass-accretion rates of white dwarfs. The agreement with observations is reasonable.

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arXiv2008

Chemical Abundances in Symbiotic Stars

We have carried out a study of the chemical abundances of $^1$H, $^4$He, $^{12}$C, $^{13}$C, $^{14}$N, $^{15}$N, $^{16}$O, $^{17}$O, $^{20}$Ne and $^{22}$Ne in symbiotic stars (SSs) by means of a population synthesis code. We find that the ratios of the number of O-rich SSs to that of C-rich SSs in our simulations are between 3.4 and 24.1, depending on the third dredge-up efficiency $λ$ and the terminal velocity of the stellar wind $v(\infty)$. The fraction of SSs with $extrinsic$ C-rich cool giants in C-rich cool giants ranges from 2.1% to 22.7%, depending on $λ$, the common envelope algorithm and the mass-loss rate. Compared with the observations, the distributions of the relative abundances of $^{12}$C/$^{13}$C vs. [C/H] of the cool giants in SSs suggest that the thermohaline mixing in low-mass stars may exist. The distributions of the relative abundances of C/N vs. O/N, Ne/O vs. N/O and He/H vs. N/O in the symbiotic nebulae indicate that it is quite common that the nebular chemical abundances in SSs are modified by the ejected materials from the hot components. Helium overabundance in some symbiotic nebulae may be relevant to a helium layer on the surfaces of white dwarf accretors.

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arXiv2006

Population synthesis for symbiotic stars with white dwarf accretors

We have carried out a detailed study of symbiotic stars with white dwarf accretors by means of a population synthesis code. We estimate the total number of symbiotic stars with white dwarf accretors in the Galaxy as 1,200 - 15,000. This range is compatible with observational estimates. Two crucial physical parameters that define the birthrate and number of symbiotic stars are the efficiency of accretion by white dwarfs (which greatly depends on the separation of components after common envelope stage and stellar wind velocity) and the mass of the hydrogen layer which the white dwarf can accumulate prior to the hydrogen ignition. The theoretical estimate of the Galactic occurrence rate of symbiotic novae ranges from about 1.3 to about 13.5 per year out of which weak symbiotic novae comprise about 0.5 to 6.0 per year, depending on the model assumptions. We simulate the distributions of symbiotic stars over orbital periods, masses of components, mass-loss rates of cool components, mass-accretion rates of hot components and luminosity of components. Agreement with observations is reasonable.

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