Breakout Time Research Articles

Magnetic field breakout in ultramassive crystallizing white dwarfs

ABSTRACT Ultramassive white dwarfs with masses $M\gtrsim 1.1\, {\rm M}_{\odot }$ probe extreme physics near the Chandrasekhar limit. Despite the rapid increase in observations, it is still unclear how many harbour carbon–oxygen (CO) versus oxygen–neon (ONe) cores. The origin of these white dwarfs and their strong magnetic fields – single stellar evolution or a stellar merger – is another open question. The steep mass–radius relation of the relativistic ultramassive white dwarfs shortens their crystallization time $t_{\rm cryst}$, such that the recently proposed crystallization dynamo mechanism may present an alternative to mergers in explaining the early appearance of magnetism in the observed population. However, the magnetic diffusion time from the convective dynamo to the white dwarf’s surface delays the magnetic field’s breakout time $t_{\rm break}\gt t_{\rm cryst}$. We compute $t_{\rm break}(M)$ for CO and ONe ultramassive white dwarfs and compare it to the local 40 pc volume-limited sample. We find that the breakout time from CO cores is too long to account for the observations. ONe crystallization dynamos remain a viable option, but their surrounding non-convective envelopes comprise only a few per cent of the total mass, such that $t_{\rm break}$ is highly sensitive to the details of stellar evolution.

Beyond the aesthetic purposes of the botilinum toxin A; The dry eye syndrome with essential blepharospasm

Botulinum A toxin injection is a method used in clinical conditions such as blepharospasm, hemifacial spasm, strabismus, migraine, hyperhidrosis, torticollis and migraine, in addition to its use for cosmetic purposes. It works by reducing the release of acetylcholine at the neuromuscular junction, and as a result, a type of paralysis occurs in the applied area for a while. Botox applied around the tear collection ducts can provide dual benefits by reducing tear loss and relieving blepharospasm. In this study, botulinum toxin A injection was applied to 33 patients with essential blepharospasm and also dry eye syndrome. Schirmer test measurement, tear breakup time (BUT) and rose bengal disappearance test were measured before the injection and at the 1st week, 1st month and 3rd month after the injection. At the same time, sampling was performed for impression cytology before the injection and at the 1st and 3rd months after the injection. Symptoms and signs of blepharospasm decreased in all patients treated with botulinum toxin A. However, the patients' Schirmer test measurements were measured immediately one week after the injection and decreased in other measurements. Tear breakout time (BUT) increased in the 1st week after the injection but decreased in the 4th week measurements. Rose bengal disappearance score increased in the 1st week after injection and returned to its previous state in the 4th week. As a result of impression cytology, no change in conjunctival cell morphology was observed before and after injection. In conclusion, essential blepharospasm and dry eye are two independent diseases, but they can occur simultaneously. Botulinum toxin A injection is a very effective method in the treatment of blepharospasm. Although it has been stated in different studies that it has a positive effect on dry eye syndrome, it was observed that it did not have such an effect in our study.

Magnetic field breakout from white dwarf crystallization dynamos

ABSTRACT A convective dynamo operating during the crystallization of white dwarfs is one of the promising channels to produce their observed strong magnetic fields. Although the magnitude of the fields generated by crystallization dynamos is uncertain, their timing may serve as an orthogonal test of this channel’s contribution. The carbon–oxygen cores of $M\approx 0.5-1.0\, {\rm M}_{\odot }$ white dwarfs begin to crystallize at an age tcryst ∝ M−5/3, but the magnetic field is initially trapped in the convection zone – deep inside the CO core. Only once a mass of mcryst has crystallized, the convection zone approaches the white dwarf’s helium layer, such that the magnetic diffusion time through the envelope shortens sufficiently for the field to break out to the surface, where it can be observed. This breakout time is longer than tcryst by a few Gyr, scaling as tbreak ∝ tcrystf−1/2, where f ≡ 1 − mcryst/M depends on the white dwarf’s initial C/O profile before crystallization. The first appearance of strong magnetic fields B ≳ 1 MG in volume-limited samples approximately coincides with our numerically computed tbreak(M) – potentially signalling crystallization dynamos as a dominant magnetization channel. However, some observed magnetic white dwarfs are slightly younger, challenging this scenario. The dependence of the breakout process on the white dwarf’s C/O profile implies that magnetism may probe the CO phase diagram, as well as uncertainties during the core helium burning phase in the white dwarf’s progenitor, such as the 12C(α, γ)16O nuclear reaction.

Design of Basketball Teaching Aid System Based on Artificial Intelligence

Abstract Artificial intelligence has penetrated every aspect of people’s lives with the rapid development of science and technology. In basketball, how to effectively utilize artificial intelligence technology to improve the effectiveness of training has become a problem worth studying. A Mediapipe-based 3D human posture domain adaptive detection method is proposed in the study by combining statistics and human limb proportion simulation. The modified SVM classification algorithm is used to compare and classify the newly acquired key point data information of the system with the standard basketball action key point data information preset by the system to judge whether the basketball action is up to the standard or not, so as to design the basketball teaching aid system based on artificial intelligence. Based on this basis, after testing the recognition performance of the system, its practical application effect is explored. The total basketball scores improved after the experiment (86.26±2.228 for the experimental group and 81.34±9.672 for the control group), but there was no significant difference (P>0.05). The control group was slower than the experimental group by 0.64 seconds and 0.77 seconds overall in the cross-step breakout time with the ball and the same-side step breakout time with the ball, respectively, indicating that the experimental group was more proficient in basketball technology. The system has been tested in various ways to meet the multiple needs of the users, meet the expected standards, and be able to be applied in real-world scenarios.

A fractional derivative model for nuclides transport in heterogeneous fractured media

Nuclide transport in fractured media involves the advection, dispersion, adsorption, etc. The dispersion and adsorption properties of the rock matrix have spatial variability, which results in an anomalous transport of nuclides. In this study, a time-fractional advection-diffusion equation (t-FADE) model is utilized to capture the sub-diffusion transport behavior with heavy-tail property, including the breakthrough curves (BTCs) of uranium and thorium transport in granite plates. Moreover, hydrodynamic dispersion of tritiated water, strontium and cesium in granite fractures are also studied. The results indicate that BTCs of nuclides transport in the granite fractures are unimodal and asymmetric. The decrease of the fractional order α reflects the stronger sub-diffusion. Furthermore, small initial velocity enhances sub-diffusion effect of nuclides and lengthens the breakout time of BTCs, which results in obvious heavy-tail phenomena. The analysis results demonstrate that the t-FADE model can accurately describe sub-diffusion behavior of nuclides transport. At last, the advantages of the t-FADE model in prediction and remediation of nuclides contamination are put forward.

GRB 221009A with an Unconventional Precursor: A Typical Two-stage Collapsar Scenario?

As the brightest gamma-ray burst (GRB) ever detected, GRB 221009A may offer a chance that reveals some interesting features that are hidden in those bursts that are not so bright. There seems to be a very weak emission with a flux of 10−8 ∼ 10−7 erg cm−2 s−1 between the first pulse (T 0 ∼ T 0 + 50 s; T 0 is the trigger time) and the main burst (which appears from T 0 + 180 s). Thus, the gap time between them is not really quiescent, and the first pulse could be taken as an unconventional precursor, which may provide a peculiar case study for GRB precursor phenomena. A two-stage collapsar scenario is proposed as the most likely origin for this burst. In this model, the jet for the precursor is produced during the initial core-collapse phase, and should be weak enough not to disrupt the star when it breaks out of the envelope, so that the fallback accretion process and the forming of the disk could continue. We present an approach in which the duration and flux both provide constraints on the luminosity (L j) and the Lorentz factor at the breakout time (Γb) of this weak jet. The estimated L j ≲ 1049 erg s−1 and Γb has an order of 10, which are well consistent with the theoretical prediction. Besides, the weak emission in the gap time could be interpreted as an MHD outflow due to a magnetically driven wind during the period from the proto-neutron-star phase to the forming of the accretion disk in this scenario.

Extensive characterization of Marshak waves observed at the LIL laser facility

We detail results of an experiment performed at the Ligne d'Intégration Laser facility aimed at studying supersonic and diffusive radiation front propagation in low-density SiO2 aerogel (20 and 40 mg/cm3) enclosed in a gold tube, driven by thermal emission from a laser-heated spherical gold cavity. The evolution of the front is studied continuously by measuring its self-emission with a 1D (one-dimensional) time-resolved soft x-ray imager. Measurement is performed along (through a 200-μm-wide observation slit) and at the exit of the tube giving access to the dynamics and the curvature of the front. Experimental results are then compared successfully to results from the 3D (three-dimensional) radiation hydrodynamics code TROLL, which shows that if continuous tracking of the front position is accessible with this experimental scheme, measurement of its maximum radiation temperature is on the contrary affected by radiation closure of the observation slit. 3D simulations also indicate that this effect can even be worsened if one includes pointing errors of the x-ray imager. Radiation temperature along the tube was then inferred by combining results from the imager to a wall shock breakout time measurement using a velocity interferometer system for any reflector and results from a broadband x-ray spectrometer used to determine the temperature at the exit of the tube. A decrease in the radiation temperature along the tube is observed, the decrease being more important for the higher SiO2 aerogel density.

Gravitational waves from the propagation of long gamma-ray burst jets

ABSTRACT Gamma-ray bursts (GRBs) are produced during the propagation of ultra-relativistic jets. It is challenging to study the jet close to the central source, due to the high opacity of the medium. In this paper, we present numerical simulations of relativistic jets propagating through a massive, stripped envelope star associated to long GRBs, breaking out of the star and accelerating into the circumstellar medium. We compute the gravitational wave (GW) signal resulting from the propagation of the jet through the star and the circumstellar medium. We show that key parameters of the jet propagation can be directly determined by the GW signal. The signal presents a first peak corresponding to the jet duration and a second peak which corresponds to the break-out time for an observer located close to the jet axis (which in turn depends on the stellar size), or to much larger times (corresponding to the end of the acceleration phase) for off-axis observers. We also show that the slope of the GW signal before and around the first peak tracks the jet luminosity history and the structure of the progenitor star. The amplitude of the GW signal is h+D ∼ hundreds to several thousands cm. Although this signal, for extragalactic sources, is outside the range of detectability of current GW detectors, it can be detected by future instruments as BBO, DECIGO, and ALIA. Our results illustrate that future detections of GW associated to GRB jets may represent a revolution in our understanding of this phenomenon.

Biomechanical Features of Backstroke to Breaststroke Transition Techniques in Age-Group Swimmers.

This study aimed to identify the biomechanical features of backstroke to breaststroke transition techniques (open, somersault, bucket, and crossover) in age-group swimmers. Eighteen preadolescent swimmers (12.2 ± 0.4 years old and 3–4 Tanner stages) underwent 4 weeks of systematic contextual interference training, comprising 16 sessions (40 min·session−1). Soon after, experimental testing was conducted where swimmers randomly performed 12 × 15 m maximal turns (composed of 7.5 m turn-in and 7.5 m turn-out of the wall segments), three in each transition technique. Kinematical, kinetic, and hydrodynamic variables were assessed with a dual-media motion capture system (12 land and 11 underwater cameras), triaxial underwater force plates, and inverse dynamics. Variables were grouped in turn-in (approach and rotation) and turn-out (wall contact, gliding, and pull-out) phases, with factor analysis used to select the variables entering on multiple regressions. For the turn-in phase, 86, 77, 89, and 87% of the variance for open, somersault, bucket, and crossover turning techniques, respectively, was accounted by the 7.5 and 2.5 m times, mean stroke length, and rotation time. For the turn-out phase, first gliding distance and time, second gliding depth, turn-out time, and dominating peak_Z push-off force accounted for 93% in open turn, while wall contact time, first gliding distance, breakout distance and time, turn-out time, dominating peak_Y push-off force, and second gliding drag coefficient accounted for 92% in a somersault turn. The foot plant index, push-off velocity, second gliding distance, and turn-out time accounted for 92% in bucket turn while breakout and turn-out time, non-dominating peak_Y and peak_Z push-off force, first and second gliding drag force and second gliding drag coefficient accounted for 90% in crossover turn, respectively. The findings in this study were novel and provided relevant biomechanical contribution, focusing on the key kinematic–temporal determinant during turn-in, rotation, and push-off efficacy, and the kinetic and hydrodynamic during turn-out, which would lead to improved backstroke to breaststroke transition techniques in 11–13 years-old age-group swimmers.

Theoretical investigations on x-ray transport in radiation transport experiments on the Shenguang-III prototype laser facility

Experiments exploring the propagation of heat waves within cylindrical CH foams were performed on the Shenguang-III prototype laser facility in 2012. In this paper, the radiation fluxes out of CH foam cylinders at different angles are analyzed theoretically using the two-dimensional radiation hydrodynamics code LARED-R. Owing to the difficulty in validating opacity and equation of state (EOS) data for high-Z plasmas, and to uncertainties in the measured radiation temperature Tr and the original foam density ρ0, multipliers are introduced to adjust the Au material parameters, Tr, and ρ0 in our simulations to better explain the measurements. The dependences of the peak radiation flux Fmax and the breakout time of the heat wave thalf (defined as the time corresponding to the radiation flux at half-maximum) on the radiation source, opacity, EOS, and ρ0 scaling factors (ηsrc, ηop, ηeos, and ηρ) are investigated via numerical simulations combined with fitting. Then, with the uncertainties in the measured Tr and ρ0 fixed at 3.6% and 3.1%, respectively, experimental data are exploited as fiducial values to determine the ranges of ηop and ηeos. It is found that the ranges of ηop and ηeos fixed by this experiment overlap partially with those found in our previous work [Meng et al., Phys. Plasmas 20, 092704 (2013)]. Based on the scaled opacity and EOS parameters, the values of Fmax and thalf obtained via simulations are in good agreement with the measurements, with maximum errors ∼9.5% and within 100 ps, respectively.

Two Steps Forward and One Step Sideways: The Propagation of Relativistic Jets in Realistic Binary Neutron Star Merger Ejecta

Abstract The association of GRB170817A with GW170817 has confirmed the long-standing hypothesis that binary neutron star (BNS) mergers are the progenitors of at least some short gamma-ray bursts (SGRBs). This connection has ushered in an era in which broadband observations of SGRBs, together with measurements of the time delay between the gravitational waves and the electromagnetic radiation, allow for probing the properties of the emitting outflow and its engine to an unprecedented detail. Because the structure of the radiating outflow is molded by the interaction of a relativistic jet with the binary ejecta, it is of paramount importance to study the system in a realistic setting. Here we present a three-dimensional hydrodynamic simulation of a relativistic jet propagating in the ejecta of a BNS merger, which were computed with a general relativistic magnetohydrodynamic simulation. We find that the jet’s centroid oscillates around the axis of the system, due to inhomogeneities encountered in the propagation. These oscillations allow the jet to find the path of least resistance and travel faster than an identical jet in smooth ejecta. In our setup the breakout time is ∼0.6 s, which is comparable to the expected central engine duration in SGRBs and possibly a non-negligible fraction of the total delay between the gravitational and gamma-ray signals. Our simulation also shows that energy is carried in roughly equal amounts by the jet and by the cocoon, and that about 20% of the injected energy is transferred to the ejecta via mechanical work.

Supernova explosions in active galactic nuclear discs

ABSTRACT Active galactic nuclei (AGNs) are prominent environments for stellar capture, growth, and formation. These environments may catalyse stellar mergers and explosive transients, such as thermonuclear and core-collapse supernovae (SNe). SN explosions in AGN discs generate strong shocks, leading to unique observable signatures. We develop an analytical model that follows the evolution of the shock propagating in the disc until it eventually breaks out. We derive the peak luminosity, bolometric light curve, and breakout time. The peak luminosities may exceed 1045 erg s−1 and last from hours to days. The brightest explosions occur in regions of reduced density: either off-plane, or in discs around low-mass central black holes (${\sim} 10^6\ \rm {M}_\odot$), or in starved subluminous AGNs. Explosions in the latter two sites are easier to observe due to a reduced AGN background luminosity. We perform suites of 1D Lagrangian radiative hydrodynamics snec code simulations to validate our results and obtain the luminosity in different bands, and 2D axisymmetric Eulerian hydrodynamics code hormone simulations to study the morphology of the ejecta and its deviation from spherical symmetry. The observed signature is expected to be a bright blue, UV or X-ray flare on top of the AGN luminosity from the initial shock breakout, while the subsequent red part of the light curve will largely be unobservable. We estimate the upper limit for the total event rate to be $\mathcal {R}\lesssim 100\ \rm yr^{-1}\ Gpc^{-3}$ for optimal conditions and discuss the large uncertainties in this estimate. Future high-cadence transient searches may reveal these events. Some existing tidal disruption event candidates may originate from AGN SNe.

1-10-60: Measuring the speed of incident response

Threat intelligence reports have started to record adversary activities with such high fidelity that it is now possible to record how rapidly they perform their actions, showing that some adversaries are moving at staggering speed in some attacks and have highly professional operations. One such report is CrowdStrike’s ‘Annual Global Threat Report’,1 in which breakout time is used as a measurement of the speed of operations of cyber adversaries. But no matter which measurement we look at, it is clear that the attackers have a very efficient operation and do not suffer from the challenges the defenders face in their day-to-day operations that prohibit them from detecting, analysing and containing an incident rapidly before it spreads. This paper will discuss the speed at which the defensive side should operate and some of the challenges with, for instance, business processes they come across in order to keep up with the pace of the attackers.

Parametric Method Applicable in Assessing Breakout Force and Time for Lifting Slender Bodies from Seabed

Abstract The article presents a parametric method applicable in assessing the suction force of a slender body to the seabed, and prognosing the body extrication time. Along with the body weight in water, the information on the suction force is essential for assessing the force needed to lift the object from the seabed. Based on the Foda theory and the resulting integral equation, which relates the maximum suction force with basic parameters of the issue of concern, the parametric method has been developed which can be widely applied in engineering practice of lifting objects. A set of discrete values of parameters selected from the range of typical values for engineering practice was the basis for developing algebraic formulas approximating the integral Foda equation for slender bodies. The included results of tests present the variability of suction force characteristics and the envelopes of maximum forces needed to extricate the body from the seabed.

Automatic annotation of local activation time was improved in idiopathic right ventricular outflow tract ventricular arrhythmia by novel electrogram "Lumipoint" algorithm.

Precise automatic annotation of local activation time (LAT) is crucial for rapid high-density activation mapping in arrhythmia. However, it is still challenging in voltage-transitional areas where local low-amplitude near-field potentials are often obscured by large far-field potentials. The aim of this study was to explore the viability and validity of automatic identification of the earliest activation (EA) in idiopathic right ventricular outflow tract ventricular arrhythmias (RVOT VAs) using a novel Lumipoint algorithm. Twenty-seven patients with RVOT VAs were mapped with Rhythmia mapping system. Lumipoint algorithms were applied to reannotate the initial activation regions retrospectively. The results showed that LATs were reannotated in 35.0 ± 11.4% points in the initial activation area from bipolar activation breakout time (BBO) to the its 40ms earlier timepoint. The automatically determined bipolar earliest activation time after Lumipoint reannotation (BEAT-lu: - 111.26 ± 12.13ms) was significantly earlier than that before (BEAT: - 108.67 ± 12.25ms, P = 0.000). Compared with manually corrected earliest activation time (EAT), the difference between EAT and BEAT-lu (DEAT-BEAT-lu: 6 (2-7) ms) was significantly smaller than that between EAT and BEAT (DEAT-BEAT/DEAT-UEA: 7 (4-11) ms, P = 0.000). The incidence of EAT and BEAT-lu being the same site was significantly higher than that between EAT and BEAT (48.15% vs 18.52%, P = 0.021). RVOT VAs often originate from voltage-transitional zone, and automatic annotation of LAT usually located at later high-amplitude far-field potential. Lumipoint algorithms could improve the accuracy of LAT automatic annotation, and it was plausible to ablate RVOT VAs just according to the automatically annotated BEAS-lu.

Jet Propagation in Neutron Star Mergers and GW170817

Abstract The gravitational wave event from the binary neutron star (BNS) merger GW170817 and the following multi-messenger observations present strong evidence for i) merger ejecta expanding with substantial velocities and ii) a relativistic jet which had to propagate through the merger ejecta. The ejecta’s expansion velocity is not negligible for the jet head motion, which is a fundamental difference from the other systems like collapsars and active galactic nuclei. Here we present an analytic model of the jet propagation in an expanding medium. In particular, we notice a new term in the expression of the breakout time and velocity. In parallel, we perform a series of over a hundred 2D numerical simulations of jet propagation. The BNS merger ejecta is prepared based on numerical relativity simulations of a BNS merger with the highest-resolution to date. We show that our analytic results agree with numerical simulations over a wide parameter space. Then we apply our analytic model to GW170817, and obtain two solid constraints on: i) the central engine luminosity as Liso, 0 ∼ 3 × 1049 − 2.5 × 1052 erg s−1, and on ii) the delay time between the merger and engine activation t0 − tm < 1.3 s. The engine power implies that the apparently-faint short gamma-ray burst (sGRB) sGRB 170817A is similar to typical sGRBs if observed on-axis.

Conditions for jet breakout in neutron stars’ mergers

ABSTRACT We consider conditions for jet breakout through ejecta following mergers of neutron stars and provide simple relations for the breakout conditions. We demonstrate that: (i) break-out requires that the isotropic-equivalent jet energy Ej exceeds the ejecta energy Eej by Ej ≥ Eej/βej, where βej = Vej/c, Vej is the maximum velocity of the ejecta. If the central engine terminates before the breakout, the shock approaches the edge of the ejecta slowly ∝ 1/t; late breakout occurs only if at the termination moment the head of the jet was relatively close to the edge. (ii) If there is a substantial delay between the ejecta’s and the jet’s launching, the requirement on the jet power increases. (iii) The forward shock driven by the jet is mildly strong, with Mach number M ≈ 5/4 (increasing with time delay td); (iii) the delay time td between the ejecta and the jet’s launching is important for $t_\mathrm{ d} \gt t_0= ({3 }/{16}) {c M_{\mathrm{ ej}} V_{\mathrm{ ej}}}/{L_\mathrm{ j}} = 1.01 {\rm \mathrm{ s}} M_{\mathrm{ ej}, -2} L_{\mathrm{ j}, 51} ^{-1} \left({\beta _{\mathrm{ ej}}} /{0.3} \right)$, where Mej is ejecta mass, Lj is the jet luminosity (isotropic equivalent). For small delays, t0 is also an estimate of the break-out time.

Parametric Method Applicable in Calculating Breakout Force and Time for Lifting Axisymmetric Objects from Seabed

Abstract The issue of calculating parameters for lifting objects of axisymmetric shapes from the seabed is studied. The article presents the results of numerical simulation examination of the equation formulated by Foda for the force needed to extricate the object from the seabed depending on soil and water parameters, extrication speed, and object diameter. The simulations were performed within the range of parameters characteristic for real applications, and their results were used for deriving approximate algebraic formulas applicable in engineering practice of lifting objects resting on seabed.

Building on the Iran Nuclear Deal for International Peace and Security

ABSTRACTAfter almost 20 months of intense negotiations, Iran six world powers – Germany, France, the United Kingdom, Russia, China, and the United States – agreed on a Joint Comprehensive Plan of Action (JCPOA) to resolve the nuclear impasse concerning Iran in July 2015. The deal provided verifiable assurances that fissile material in Iran could not be diverted toward weaponization purposes; the highest standards on nuclear transparency and inspections ever negotiated; and the lifting of US and United Nations nuclear-related sanctions on Iran. The agreement was welcomed by the international community and endorsed by a UN Security Council resolution.This article examines the major factors that led Iran and the global powers to reach a deal. Those factors included each side's willingness to cash in its main bargaining chips (a short breakout time for Iran and sanctions for the United States), a change in leadership in each country, and a shifting geopolitical context. Foremost, however, was the US willingness to change its demands of Iran from no nuclear enrichment to no nuclear bomb. The JCPOA has had major implications for the global powers and Iran, affecting especially the bilateral US -Iran relationship, the regional security situations, and US domestic politics.

Study on laser-irradiated Au plasmas by detailed configuration accounting atomic physics

We coupled the one-dimensional multi-group radiation hydrodynamic code RDMG with the MBDCA atomic physics package, which uses the Matrix-Block Method to solve the coupled rate equations of the Detailed Configuration Accounting (DCA) non-LTE model, and applied the coupled code RDMG-MBDCA with different flux limiters fe to simulate a laser-irradiated CH-tamped Au disk experiment at the SGII laser facility. From our simulations, we found that a higher fe leads to faster laser ablation, earlier x-ray breakout time with a higher maximum x-ray flux, and an x-ray spectrum with a higher intensity. However, for the same fe, the simulation from RDMG with the DCA model shows a slower electron thermal conduction between the laser absorption region and the electron thermal conduction than that with the average-atom model. From our investigation, we can say that it is the lower ionization from DCA in the electron thermal conduction region which causes the slower electron thermal conduction between the two regions. The electron thermal conduction from DCA can be increased remarkably when the atomic processes of dielectronic capture and auto-ionization are turned off in simulation. This indicates that the atomic transition rate coefficients are important in determining the heat conduction and the plasma status for laser generated plasmas.