分类： 天文学 >> 星系和宇宙学 提交时间： 2023-05-24
摘要：We analyse $H(z)$ parameter data with some conditions by using Lagrange mean value theorem in Calculus. We find that: (1) there exists at least one decelerated phase at 1 $ sigma$ confidence level in the redshift range $(0.38, 0.59)$; (2) the equation of motion of dark energy may be less than $-1$ at 1 $ sigma$ confidence level at some redshifts in the redshift range $(1.3, 1.53)$; (3) there exists at least one accelerated phase at 1 $ sigma$ confidence level in the redshift range $(1.037, 1.944)$. These results may provide possible evidences for physics beyond $ Lambda$CDM.
分类： 天文学 >> 天体物理学 提交时间： 2023-05-16
摘要：日冕是太阳大气活动的关键区域, 是日地空间天气的源头. 受观测限制, 人们对日冕低层大气等离子体结构和磁场状态的研究非常欠缺, 国际上对于可见光波段日冕低层大气的亮度分层研究很少. 本文利用丽江日冕仪YOGIS(Yunnan Green-line Imaging System) 的日冕绿线（FeXIV 5303 Å）观测资料, 对内日冕区域（1.03R⊙-1.25R⊙）亮结构及其中冕环进行了有效的强度衰减分析. 本文通过对亮结构的强度在太阳径向高度上进行了指数衰减拟合, 比较这些拟合结果发现所得到的静态内冕环的衰减指数在一固定值附近. 然后将比较明显的冕环提取出来, 通过对不同高度的强度进行相同的指数拟合, 得出的衰减指数与亮结构中也比较相近, 这对进一步研究日冕中的各项物理参数演化提供了参考.
分类： 天文学 >> 天文学 提交时间： 2023-03-13 合作期刊: 《天文研究与技术》
摘要：本文给出了在连续式旋转波片调制模式下的傅里叶分析的推导过程和解调公式,并利用理论偏振轮廓对公式的准确性进行了验证。分别采用了傅里叶分析和解调矩阵两种解调方法定量模拟了在连续式调制模式下波片的初始方位角误差、旋转定位误差以及探测器曝光过程中时间差占比三个因素对测量精度的影响。主要结论是：(1)简单的傅里叶分析不再适用于连续式调制的结果解调。文中给出的新傅里叶分析方法与解调矩阵方法在进行误差分析时，可以得到基本一致的结果。(2)考虑初始方位角误差引起的影响，我们发现对于线偏振信号来说，采用傅里叶分析和解调矩阵可得到非常一致的结果，而对于圆偏振来说，基于解调矩阵的方法得到的结果误差相对较小。但是两种解调方法都反映出初始方位角误差对圆偏振和线偏振产生的影响是一致，且相对误差的大小与偏振信号本身的强弱有关。初始方位角的误差要求在十几角秒量级才能满足结果的相对误差在10-3量级以下。(3)考虑旋转定位误差引起的影响时，我们发现采用傅里叶分析和解调矩阵得到的结果非常接近。两者同时都显示出旋转定位误差对线偏振信号造成的影响更为明显，且相对误差的大小也与信号的强弱有关。当波片的重复定位精度在10''左右时，对10-2量级的弱偏振信号来说，测量误差也能在10-3的量级左右。从这一点上，我们发现连续式调制模式对波片旋转的定位精度要求要明显高于步进式调制模式。(4)两种解调方法的结果均显示，在连续式调制模式下，波片的调制周期与探测器曝光时长的时间差(∆)会造成线偏振信号之间的串扰，即时间差占比(∆/T)对线偏振信号造成的影响比对圆偏振信号的影响更为明显。当∆/T小于1%时，线偏振信号相对误差达到10-3量级。
分类： 天文学 >> 天文学 提交时间： 2023-03-13 合作期刊: 《天文研究与技术》
摘要：针对空间目标与恒星的近距离强干扰和瞬间遮挡干扰，不易精确捕获目标位置。提出用卡尔曼滤波预测目标位置并跟踪目标，跟踪波门用改进自适应的可变波门。同时设计新的强干扰和瞬间遮挡目标的预判和跟踪方法，当预判到此类目标时，将卡尔曼滤波的预测值作为观测值跟踪目标，并用目标预测质心对波门质心进行限定修正，从而捕获有用的观测数据。实验发现，该方法能稳健跟踪强干扰和瞬间遮挡目标，提升空间目标的跟踪精度，降低数据错误率，提高数据质量，为捕获轨道位置提供更多更有用的数据。该方法程序运行速率快，具有一定的适用性和科学价值。
分类： 天文学 >> 天文学 提交时间： 2023-03-13 合作期刊: 《天文研究与技术》
摘要：月面低频射电观测具有巨大科学发现潜力，有望揭开宇宙黑暗和黎明时代秘密。本文针对于月背低频观测的天线及其匹配电路提出了一种新的设计方案，利用非福斯特匹配电路，大大减小了天线的物理尺寸，使之结构轻巧便于月面部署。首先，设计了一种轻巧、宽温度范围、具有易延展性、可折叠性、便于在月面部署的电小薄膜天线，其具有很好的全向性，在4-8MHz内增益小于1.92dB，半波束宽度大于83°，然后利用加载非福斯特匹配电路来改善其阻抗性能，将天线的电抗从高达-985.3Ω优化到-16.5Ω以内，最后采用等效电路进行了阻抗和噪声实测，其噪声功率密度水平在绝大部分频率范围内小于-150dBm/Hz，证实了该方案的可行性。
分类： 天文学 >> 天文学 提交时间： 2023-03-13 合作期刊: 《天文研究与技术》
摘要：提出了一种基于Xception结构的天体目标自动分类算法，该算法可有效应用于星系、恒星和类星体的自动分类问题。算法以Xception为基础框架，通过选择最优激活函数，加入注意力机制等方式进行改进。随机选择SDSS-DR16测光图像数据中的11543个星系、10490个类星体和11967个恒星共34000个观测源g，r和i的3个波段的图像作为实验数据，并设计多组实验进行算法验证和测试，综合分析所有实验结果得出本文算法在准确率、精确率、召回率和F1分数等关键指标分别达到了90.26%，90.01%，89.86%和89.85%。相同数据集与其他13种经典和流行的卷积神经网络（Convolutional Neural Network, CNN）算法的实验测试结果对比表明，本文提出的Xception-AS算法具有更加优异的分类性能，证明本文算法在解决天体目标自动分类问题具有优越性。
分类： 天文学 >> 天体物理学 提交时间： 2023-02-21
Chaojun Wang
B. Luo
W. N. Brandt
D. M. Alexander
F. E. Bauer
S. C. Gallagher
Jian Huang
Hezhen Liu
D. Stern
摘要：We utilize recent NuSTAR observations (co-added depth ≈55-120 ks) of PG 1001+054, PG 1254+047, and PHL 1811 to constrain their hard X-ray (≳5 keV) weakness and spectral shapes, and thus to investigate the nature of their extreme X-ray weakness. These quasars showed very weak soft X-ray emission, and they were proposed to be intrinsically X-ray weak, with the X-ray coronae producing weak continuum emission relative to their optical/UV emission. However, the new observations suggest an alternative explanation. The NuSTAR 3-24 keV spectral shapes for PG 1001+054 and PHL 1811 are likely flat (effective power-law photon indices \Gamma_{\rm eff}=1.0^{+0.5}_{-0.6} and \Gamma_{\rm eff}=1.4^{+0.8}_{-0.7}, respectively), while the shape is nominal for PG 1254+047 (\Gamma_{\rm eff}=1.8\pm0.3). PG 1001+054 and PHL 1811 are significantly weak at hard X-ray energies (by factors of ≈26-74 at rest-frame 8 keV) compared to the expectations from their optical/UV emission, while PG 1254+047 is only hard X-ray weak by a factor of ≈3. We suggest that X-ray obscuration is present in all three quasars. We propose that, as an alternative to the intrinsic X-ray weakness + X-ray obscuration scenario, the soft and hard X-ray weakness of these quasars can be uniformly explained under an obscuration-only scenario. This model provides adequate descriptions of the multi-epoch soft and hard X-ray data of these quasars, with variable column density and leaked fraction of the partial-covering absorber. We suggest that the absorber is the clumpy dust-free wind launched from the accretion disk. These quasars probably have super-Eddington accretion rates that drive powerful and high-density winds.
分类： 天文学 >> 星系和宇宙学 提交时间： 2023-02-21
Qiuhan He
Ran Li
Carlos S. Frenk
James Nightingale
Shaun Cole
Nicola C. Amorisco
Richard Massey
Andrew Robertson
Amy Etherington
Aristeidis Amvrosiadis
Xiaoyue Cao
摘要：We rederive the number density of intervening line-of-sight haloes relative to lens subhaloes in galaxy-galaxy strong lensing observations, where these perturbers can generate detectable image fluctuations. Previous studies have calculated the detection limit of a line-of-sight small-mass dark halo by comparing the lensing deflection angles it would cause, to those caused by a subhalo within the lens. However, this overly simplifies the difference in observational consequences between a subhalo and a line-of-sight halo. Furthermore, it does not take into account degeneracies between an extra subhalo and the uncertain properties of the main lens. More in keeping with analyses of real-world observations, we regard a line-of-sight halo as detectable only if adding it to a smooth model generates a statistically significant improvement in the reconstructed image. We find that the number density of detectable line-of-sight perturbers has been overestimated by as much as a factor of two in the previous literature. For typical lensing geometries and configurations, very deep imaging is sensitive to twice as many line-of-sight perturbers as subhaloes, but moderate depth imaging is sensitive to only slightly more line-of-sight perturbers than subhaloes.
分类： 天文学 >> 天体物理学 提交时间： 2023-02-21
Weicheng Zang
Youn Kil Jung
Hongjing Yang
Xiangyu Zhang
Andrzej Udalski
Jennifer C. Yee
Andrew Gould
Shude Mao
摘要：We present the analysis of seven microlensing planetary events with planet/host mass ratios q < 10^{-4}: KMT-2017-BLG-1194, KMT-2017-BLG-0428, KMT-2019-BLG-1806, KMT-2017-BLG-1003, KMT-2019-BLG-1367, OGLE-2017-BLG-1806, and KMT-2016-BLG-1105. They were identified by applying the Korea Microlensing Telescope Network (KMTNet) AnomalyFinder algorithm to 2016--2019 KMTNet events. A Bayesian analysis indicates that all the lens systems consist of a cold super-Earth orbiting an M or K dwarf. Together with 17 previously published and three that will be published elsewhere, AnomalyFinder has found a total of 27 planets that have solutions with q < 10^{-4} from 2016--2019 KMTNet events, which lays the foundation for the first statistical analysis of the planetary mass-ratio function based on KMTNet data. By reviewing the 27 planets, we find that the missing planetary caustics problem in the KMTNet planetary sample has been solved by AnomalyFinder. We also find a desert of high-magnification planetary signals (A≳65), and a follow-up project for KMTNet high-magnification events could detect at least two more q < 10^{-4} planets per year and form an independent statistical sample.
分类： 天文学 >> 天体物理学 提交时间： 2023-02-21
H. Hu
M. Kramer
D. J. Champion
N. Wex
A. Parthasarathy
T. T. Pennucci
N. K. Porayko
W. van Straten
V. Venkatraman Krishnan
M. Burgay
P. C. C. Freire
R. N. Manchester
A. Possenti
I. H. Stairs
M. Bailes
S. Buchner
A. D. Cameron
F. Camilo
M. Serylak
摘要：The Double Pulsar, PSR J0737-3039A/B, has offered a wealth of gravitational experiments in the strong-field regime, all of which GR has passed with flying colours. In particular, among current gravity experiments that test photon propagation, the Double Pulsar probes the strongest spacetime curvature. Observations with MeerKAT and, in future, the SKA can greatly improve the accuracy of current tests and facilitate tests of NLO contributions in both orbital motion and signal propagation. We present our timing analysis of new observations of PSR J0737-3039A, made using the MeerKAT telescope over the last 3 years. The increased timing precision offered by MeerKAT yields a 2 times better measurement of Shapiro delay parameter s and improved mass measurements compared to previous studies. In addition, our results provide an independent confirmation of the NLO signal propagation effects and already surpass the previous measurement from 16-yr data by a factor of 1.65. These effects include the retardation effect due to the movement of B and the deflection of the signal by the gravitational field of B. We also investigate novel effects which are expected. For instance, we search for potential profile variations near superior conjunctions caused by shifts of the line-of-sight due to latitudinal signal deflection and find insignificant evidence with our current data. With simulations, we find that the latitudinal deflection delay is unlikely to be measured with timing because of its correlation with Shapiro delay. Furthermore, although it is currently not possible to detect the expected lensing correction to the Shapiro delay, our simulations suggest that this effect may be measured with the full SKA. Finally, we provide an improved analytical description for the signal propagation in the Double Pulsar system that meets the timing precision expected from future instruments such as the full SKA.
分类： 天文学 >> 天文学 提交时间： 2023-02-21
Yali Shao
Ran Wang
Axel Weiss
Jeff Wagg
Chris L. Carilli
Michael A. Strauss
Fabian Walter
Pierre Cox
Xiaohui Fan
Karl M. Menten
Desika Narayanan
Dominik Riechers
Frank Bertoldi
Alain Omont
Linhua Jiang
摘要：We present Atacama Large Millimeter/submillimeter Array (ALMA) sub-kiloparsec- to kiloparsec-scale resolution observations of the [C ii], CO (9–8), and OH+ (11–01) lines along with their dust continuum emission toward the far-infrared (FIR) luminous quasar SDSS J231038.88+185519.7 at z = 6.0031, to study the interstellar medium distribution, the gas kinematics, and the quasar-host system dynamics. We decompose the intensity maps of the [C ii] and CO (9–8) lines and the dust continuum with two-dimensional elliptical Sérsic models. The [C ii] brightness follows a flat distribution with a Sérsic index of 0.59. The CO (9–8) line and the dust continuum can be fit with an unresolved nuclear component and an extended Sérsic component with a Sérsic index of ∼1, which may correspond to the emission from an active galactic nucleus dusty molecular torus and a quasar host galaxy, respectively. The different [C ii] spatial distribution may be due to the effect of the high dust opacity, which increases the FIR background radiation on the [C ii] line, especially in the galaxy center, significantly suppressing the [C ii] emission profile. The dust temperature drops with distance from the center. The effective radius of the dust continuum is smaller than that of the line emission and the dust mass surface density, but is consistent with that of the star formation rate surface density. This may indicate that the dust emission is a less robust tracer of the dust and gas distribution but is a decent tracer of the obscured star formation activity. The OH+ (11–01) line shows a P-Cygni profile with an absorption at ∼–400 km/s, which may indicate an outflow with a neutral gas mass of (6.2 ± 1.2) × 108 M along the line of sight. We employed a three-dimensional tilted ring model to fit the [C ii] and CO (9–8) data cubes. The two lines are both rotation dominated and trace identical disk geometries and gas motions. This suggest that the [C ii] and CO (9–8) gas are coplanar and corotating in this quasar host galaxy. The consistent circular velocities measured with [C ii] and CO (9–8) lines indicate that these two lines trace a similar gravitational potential. We decompose the circular rotation curve measured from the kinematic model fit to the [C ii] line into four matter components (black hole, stars, gas, and dark matter). The quasar-starburst system is dominated by baryonic matter inside the central few kiloparsecs. We constrain the black hole mass to be 2.97+0.51 −0.77 × 109 M ; this is the first time that the dynamical mass of a black hole has been measured at z ∼ 6. This mass is consistent with that determined using the scaling relations from quasar emission lines. A massive stellar component (on the order of 109 M ) may have already existed when the Universe was only ∼0.93 Gyr old. The relations between the black hole mass and the baryonic mass of this quasar indicate that the central supermassive black hole may have formed before its host galaxy.
分类： 天文学 >> 星系和宇宙学 提交时间： 2023-02-21
摘要：In this paper we consider the effects of adding curvature in extended cosmologies involving a free-to-vary neutrino sector and different parametrizations of Dark Energy (DE). We make use of the Planck 2018 cosmic microwave background temperature and polarization data, Baryon Acoustic Oscillations and Pantheon type Ia Supernovae data. Our main result is that a non-flat Universe cannot be discarded in light of the current astronomical data, because we find an indication for a closed Universe in most of the DE cosmologies explored in this work. On the other hand, forcing the Universe to be flat can significantly bias the constraints on the equation of state of the DE component and its dynamical nature.
分类： 天文学 >> 星系和宇宙学 提交时间： 2023-02-21
摘要：Interstellar (ISM) and circumgalactic medium (CGM) around galaxies are linked to several physical processes that drive galaxy evolution. For example, the X-ray emission from the CGM gas around ellipticals has been linked to the AGN feedback occurring in the host. Upcoming telescopes such as HUBS, with ~ 1 eV resolution, can provide us with deep insights about the hot gas properties of such galaxies thus constrain these processes. In this project, we discuss X-ray emission of the ISM and CGM of elliptical galaxies simulated using MACER code. We generate X-ray emission data from the MACER simulations with various feedback models and produce mock observations for an instrument with high spectral resolution, which is a necessary step of selecting sources for the future observations with planned mission such as HUBS. More importantly, we establish connections between the physics of AGN and stellar feedback with the emission spectra from the ISM and CGM to investigate the possibility of using observations to constrain feedback models. We fit the X-ray spectra from these simulations with standard fitting procedures and compare the retrieved physical properties with their counterparts from the simulations to understand whether the future high-resolution observations can reliably reveal the properties of the gas in the galaxies.
分类： 天文学 >> 星系和宇宙学 提交时间： 2023-02-21
Y. T. Yan
C. Henkel
K. M. Menten
Y. Gong
H. Nguyen
J. Ott
A. Ginsburg
T. L. Wilson
A. Brunthaler
A. Belloche
J. S. Zhang
N. Budaiev
D.Jeff
摘要：We report the discovery of widespread maser emission in non-metastable inversion transitions of NH_3 toward various parts of the Sagittarius B2 molecular cloud/star forming region complex: We detect masers in the J,K= (6,3), (7,4), (8,5), (9,6), and (10,7) transitions toward Sgr B2(M) and Sgr B2(N), an NH_3 (6,3) maser in Sgr B2(NS), and NH_3 (7,4), (9,6), and (10,7) masers in Sgr B2(S). With the high angular resolution data of the Karl G. Jansky Very Large Array (JVLA) in A-configuration we identify 18 maser spots. Nine maser spots arise from Sgr B2(N), one from Sgr B2(NS), five from Sgr B2(M), and three in Sgr B2(S). Compared to our Effelsberg single dish data, the JVLA data indicate no missing flux. The detected maser spots are not resolved by our JVLA observations. Lower limits to the brightness temperature are >3000~K and reach up to several 10^5~K, manifesting the lines' maser nature. In view of the masers' velocity differences with respect to adjacent hot molecular cores and/or UCH{\scriptsize II} regions, it is argued that all the measured ammonia maser lines may be associated with shocks caused either by outflows or by the expansion of UCH{\scriptsize II} regions. Overall, Sgr B2 is unique in that it allows us to measure many NH_3 masers simultaneously, which may be essential to elucidate their so far poorly understood origin and excitation.
分类： 天文学 >> 星系和宇宙学 提交时间： 2023-02-21
Guang Yang
W. N. Brandt
David M. Alexander
Médéric Boquien
Qingling Ni
Casey Papovich
Justin S. Spilker
Fabio Vito
Jonelle L. Walsh
Chengpeng Zhang
摘要：Recent studies have revealed a strong relation between sample-averaged black-hole (BH) accretion rate (BHAR) and star formation rate (SFR) among bulge-dominated galaxies, i.e., "lockstep" BH-bulge growth, in the distant universe. This relation might be closely related to the BH-bulge mass correlation observed in the local universe. To understand further BH-bulge coevolution, we present ALMA CO(2-1) or CO(3-2) observations of 7 star-forming bulge-dominated galaxies at z=0.5-2.5. Using the ALMA data, we detect significant (>3σ) CO emission from 4 objects. For our sample of 7 galaxies, we measure (or constrain with upper limits) their CO line fluxes and estimate molecular gas masses (M_{gas}). We also estimate their stellar masses (M_{star}) and SFRs by modelling their spectral energy distributions (SEDs). Using these physical properties, we derive the gas-depletion timescales (t_{dep} = M_{gas}/SFR) and compare them with the bulge/BH growth timescales (t_{grow} = M_{star}/SFR \sim M_{BH}/BHAR). Our sample generally has t_{dep} shorter than t_{grow} by a median factor of ≳4, indicating that the cold gas will be depleted before significant bulge/BH growth takes place. This result suggests that the BH-bulge lockstep growth is mainly responsible for maintaining their mass relation, not creating it. We note that our sample is small and limited to z<2.5; JWST and ALMA will be able to probe to higher redshifts in the near future.
分类： 天文学 >> 天体物理学 分类： 物理学 >> 地球物理学、天文学和天体物理学 提交时间： 2023-02-17
摘要：
According to the ΛCDM cosmological model, dark matter has a very long history
and remains a puzzle. X-ray observations suggest that the best candidate of dark matter is
cosmic plasma. It is only because in the ΛCDM cosmological model, the mass of the cosmic
plasma is limited to less than 5% of the critical mass of the universe (i.e. Ωb < 0:05) in
order to guarantee the conjecture that the observed CMB is a remnant of the Big Bang with a
perfect blackbody spectrum, that this X-ray observational evidence is unreasonably ignored.
If astrophysicists could discard the unreasonable assumption: i.e. Ωb < 0:05, then the dark
matter puzzle would be easy to solve. Dark matter is actually cosmic plasma
分类： 天文学 >> 天文学 提交时间： 2023-01-18 合作期刊: 《天文研究与技术》
摘要：本文基于Python设计和实现自动测光程序。首先扫描文件名实现文件分类；然后进行数据检查、预处理与孔径测光，并保存测光数据；最终由观测者指定目标星与比较星，程序从测光结果中提取相应星等与观测时间等数据，获得基于较差测光法的光变曲线。为解决数据提取中星图匹配问题，提出自动追踪移动目标的基于向量特征星图匹配算法，能自动匹配偏移较大的星图，并跟踪不断移动的小行星。使用本程序分别处理双星和小行星观测数据，并与IRAF（Image Reducation and Analysis Facility）测光结果比较，测光结果最大偏差分别为0.04mag和0.043mag，标准偏差分别为±0.005mag和±0.007mag。
分类： 天文学 >> 天文学 提交时间： 2023-01-18 合作期刊: 《天文研究与技术》
摘要：随着天文观测技术的飞速发展，天文数据处理软件日趋复杂，天文数据处理环境的部署与管理日渐繁琐。利用容器技术将脉冲星数据处理环境封装成容器镜像并建立私有镜像库，科研人员可以根据数据处理需求选择镜像，实现数据处理环境的快速部署。利用实体计算机、虚拟机和容器中对脉冲星基带数据进行相干消色散处理，对比不同平台的资源利用率与数据处理效率。实验结果表明，容器的性能与实体计算机相近；在多任务并发的数据处理测试中，容器的资源分配更加合理，相较虚拟机可以提高计算资源利用效率。在新疆天文台脉冲星数据处理服务器上实现了基于容器的数据处理架构部署，设计并开发了容器管理图形用户界面，通过优化多用户登录、身份验证、数据卷挂载管理等功能，提高利用容器技术进行天文数据处理的效率。
分类： 天文学 >> 天文学 提交时间： 2023-01-17 合作期刊: 《天文研究与技术》
摘要：耀变体是一种非常活跃的活动星系核，研究它的有效谱指数是认识其内部结构和辐射机制的有效方法。文中数据采用目前已公布出的SMARTS数据库数据,共682组具有B,V,R,J,K波段的准同时性的观测数据，用LombScargle Periodogram（LSP）方法研究了其有效谱指数的特性，结果得出3C 454.3光学和红外波段光变之间呈正相关；光学和红外波段光变存在2个主导周期，分别约为1.2yr，4.5yr；双黑洞结构模型中双黑洞质量比为2/1 。
分类： 天文学 >> 天文学 提交时间： 2023-01-17 合作期刊: 《天文研究与技术》
摘要：射电天文在HF-VHF频段采用天线组阵的方式进行观测，根据平方公里阵（Square Kilometre Array, SKA）的要求，每个阵列单元天线的增益、结构一致性、稳定性、阻抗变化趋势和极化纯度等方面需要达到较高指标，才能满足太阳、木星、再电离纪元等多种测量在极化测量、天线跟踪稳定性以及接收机宽带匹配等方面的需求。根据SKA requirement 2165：极化纯度（polarization purity）2135–38 和每极化方向灵敏度（sensitivity per polarization）2814–15提出的性能需求,以及在总结原有设计的经验后，针对10-90MHz频段，设计了一种适用于HF-VHF的新型倒“V”型栅板偶极子天线，具有重量轻，风阻小等优点，在10-90MHz的超宽频段内阻抗变化缓慢、极化纯度良好。其中，在阻抗变化方面，天线的阻抗实部从0.8Ω到631.132Ω变化，优于低频射电阵列（Low Frequency Array, LOFAR）的低频阵列天线，降低了接收机匹配难度和噪声；极化纯度方面，天线整体轴比小于0.41dB，对于太阳射电爆发等强极化信号具有良好的极化隔离度。
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