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The branch-cut quantum gravity with a self-coupling inflation scalar field: Dynamical equations 带有自耦合膨胀标量场的分支切割量子引力:动力学方程
IF 0.9 4区 物理与天体物理
Astronomische Nachrichten Pub Date : 2023-12-12 DOI: 10.1002/asna.20230152
Fridolin Weber, Peter O. Hess, Benno Bodmann, José de Freitas Pacheco, Dimiter Hadjimichef, Marcelo Marzola, Geovane Naysinger, Moisés Razeira, César A. Zen Vasconcellos
{"title":"The branch-cut quantum gravity with a self-coupling inflation scalar field: Dynamical equations","authors":"Fridolin Weber,&nbsp;Peter O. Hess,&nbsp;Benno Bodmann,&nbsp;José de Freitas Pacheco,&nbsp;Dimiter Hadjimichef,&nbsp;Marcelo Marzola,&nbsp;Geovane Naysinger,&nbsp;Moisés Razeira,&nbsp;César A. Zen Vasconcellos","doi":"10.1002/asna.20230152","DOIUrl":"10.1002/asna.20230152","url":null,"abstract":"<p>This article focuses on the implications of the recently developed commutative formulation based on branch-cutting cosmology, the Wheeler–DeWitt equation, and Hořava–Lifshitz quantum gravity. Assuming a mini-superspace of variables, we explore the impact of an inflaton-type scalar field <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>ϕ</mi>\u0000 <mrow>\u0000 <mo>(</mo>\u0000 <mi>t</mi>\u0000 <mo>)</mo>\u0000 </mrow>\u0000 </mrow>\u0000 <annotation>$$ phi (t) $$</annotation>\u0000 </semantics></math> on the dynamical equations that describe the trajectories evolution of the scale factor of the Universe, characterized by the dimensionless helix-like function <math>\u0000 <semantics>\u0000 <mrow>\u0000 <msup>\u0000 <mi>ln</mi>\u0000 <mrow>\u0000 <mo>−</mo>\u0000 <mn>1</mn>\u0000 </mrow>\u0000 </msup>\u0000 <mrow>\u0000 <mo>[</mo>\u0000 <mrow>\u0000 <mi>β</mi>\u0000 <mrow>\u0000 <mo>(</mo>\u0000 <mi>t</mi>\u0000 <mo>)</mo>\u0000 </mrow>\u0000 </mrow>\u0000 <mo>]</mo>\u0000 </mrow>\u0000 </mrow>\u0000 <annotation>$$ {ln}^{-1}left[beta (t)right] $$</annotation>\u0000 </semantics></math>. This scale factor characterizes a Riemannian foliated spacetime that topologically overcomes the big bang and big crunch singularities. Taking the Hořava–Lifshitz action as our starting point, which depends on the scalar curvature of the branched Universe and its derivatives, with running coupling constants denoted as <math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>g</mi>\u0000 <mi>i</mi>\u0000 </msub>\u0000 </mrow>\u0000 <annotation>$$ {g}_i $$</annotation>\u0000 </semantics></math>, the commutative quantum gravity approach preserves the diffeomorphism property of General Relativity, maintaining compatibility with the Arnowitt–Deser–Misner formalism. We investigate both chaotic and nonchaotic inflationary scenarios, demonstrating the sensitivity of the branch-cut Universe's dynamics to initial conditions and parameterizations of primordial matter content. The results suggest a continuous connection of Riemann surfaces, overcoming primordial singularities and exhibiting diverse evolutionary behaviors, from big crunch to moderate acceleration.</p>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"345 2-3","pages":""},"PeriodicalIF":0.9,"publicationDate":"2023-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asna.20230152","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138692191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A short review of the pulsar magnetic inclination angles (II) 脉冲星磁倾角简评(二)
IF 0.9 4区 物理与天体物理
Astronomische Nachrichten Pub Date : 2023-12-11 DOI: 10.1002/asna.20230167
Biao-Peng Li, Wen-Qi Ma, Zhi-Fu Gao
{"title":"A short review of the pulsar magnetic inclination angles (II)","authors":"Biao-Peng Li,&nbsp;Wen-Qi Ma,&nbsp;Zhi-Fu Gao","doi":"10.1002/asna.20230167","DOIUrl":"10.1002/asna.20230167","url":null,"abstract":"<p>The pulsar magnetic inclination angle is a key parameter for pulsar physics. It influences the observable properties of pulsars, such as the pulse beam width, braking index, polarization, and emission geometry. In this study, we give a brief overview of the current state of knowledge and research on this parameter and its implications for the internal physics of pulsars. We use the observed pulsar data of magnetic inclination angle and braking index to constrain the star's number of precession cycles, <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>ξ</mi>\u0000 </mrow>\u0000 <annotation>$$ xi $$</annotation>\u0000 </semantics></math>, which reflects the interaction between superfluid neutrons and other particles inside a neutron star (NS). We apply the method proposed by Cheng et al. (Cheng, Q., Zhang, S. N., Zheng, X. P., &amp; Fan, X. L., 2019, <i>Phys. Rev. D</i>, 99, 083011) to analyze the data of PSR J2013 + 3845 and obtain the constraints for <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>ξ</mi>\u0000 </mrow>\u0000 <annotation>$$ xi $$</annotation>\u0000 </semantics></math> ranging from <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>2</mn>\u0000 <mo>.</mo>\u0000 <mn>393</mn>\u0000 <mo>×</mo>\u0000 <mn>1</mn>\u0000 <msup>\u0000 <mrow>\u0000 <mn>0</mn>\u0000 </mrow>\u0000 <mrow>\u0000 <mn>5</mn>\u0000 </mrow>\u0000 </msup>\u0000 </mrow>\u0000 <annotation>$$ 2.393times 1{0}^5 $$</annotation>\u0000 </semantics></math> to <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>1</mn>\u0000 <mo>.</mo>\u0000 <mn>268</mn>\u0000 <mo>×</mo>\u0000 <mn>1</mn>\u0000 <msup>\u0000 <mrow>\u0000 <mn>0</mn>\u0000 </mrow>\u0000 <mrow>\u0000 <mn>6</mn>\u0000 </mrow>\u0000 </msup>\u0000 </mrow>\u0000 <annotation>$$ 1.268times 1{0}^6 $$</annotation>\u0000 </semantics></math>. And further analysis suggests that the internal magnetic field structure of PSR J2013 + 3845 is likely dominated by toroidal components. This study may help us understand the process of internal viscous dissipation and the related evolution of the inclination angles of pulsars, and may have important implications for the study of continuous gravitational wave emissions from NS.</p>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"345 2-3","pages":""},"PeriodicalIF":0.9,"publicationDate":"2023-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138692261","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Repeating fast radio bursts reveal the secret of pulsar magnetospheric activity 重复的快速射电暴揭示了脉冲星磁层活动的秘密
IF 0.9 4区 物理与天体物理
Astronomische Nachrichten Pub Date : 2023-12-05 DOI: 10.1002/asna.20230153
Renxin Xu, Weiyang Wang
{"title":"Repeating fast radio bursts reveal the secret of pulsar magnetospheric activity","authors":"Renxin Xu,&nbsp;Weiyang Wang","doi":"10.1002/asna.20230153","DOIUrl":"10.1002/asna.20230153","url":null,"abstract":"<p>The puzzling mechanism of coherent radio emission remains unknown, but fortunately, repeating fast radio bursts (FRBs) provide a precious opportunity, with extremely bright subpulses created in a clear and vacuum-like pulsar magnetosphere. FRBs are millisecond-duration signals that are highly dispersed at distant galaxies but with uncertain physical origin(s). Coherent curvature radiation by bunches has already been proposed for repeating FRBs. The charged particles are created during central star's quakes, which can form bunches streaming out along curved magnetic field lines, so as to trigger FRBs. The nature of narrow-band radiation with time-frequency drifting can be a natural consequence that bunches could be observed at different times with different curvatures. Additionally, high linear-polarization can be seen if the line of sight is confined to the beam angle, whereas the emission could be highly circular-polarized if off-beam. It is also discussed that pulsar surface may be full of small hills (i.e., zits) which would help producing bulk of energetic bunches for repeating FRBs as well as for rotation-powered pulsars.</p>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"345 2-3","pages":""},"PeriodicalIF":0.9,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138530363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Differential rotation in compact objects with hyperons and delta isobars 具有超子和等压线的致密物体的微分旋转
IF 0.9 4区 物理与天体物理
Astronomische Nachrichten Pub Date : 2023-12-03 DOI: 10.1002/asna.20230160
Delaney Farrell, Fridolin Weber, Jia Jie Li, Armen Sedrakian
{"title":"Differential rotation in compact objects with hyperons and delta isobars","authors":"Delaney Farrell,&nbsp;Fridolin Weber,&nbsp;Jia Jie Li,&nbsp;Armen Sedrakian","doi":"10.1002/asna.20230160","DOIUrl":"10.1002/asna.20230160","url":null,"abstract":"<p>Neutron stars may experience differential rotation on short, dynamical timescales following extreme astrophysical events like binary neutron star mergers. In this work, the masses and radii of differentially rotating neutron star models are computed. We employ a set of equations of states for dense hypernuclear and <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>Δ</mi>\u0000 </mrow>\u0000 <annotation>$$ Delta $$</annotation>\u0000 </semantics></math>-admixed-hypernuclear matter obtained within the framework of CDF theory in the relativistic Hartree-Fock (RHF) approximation. Results are shown for varying meson-<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>Δ</mi>\u0000 </mrow>\u0000 <annotation>$$ Delta $$</annotation>\u0000 </semantics></math> couplings, or equivalently the <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>Δ</mi>\u0000 </mrow>\u0000 <annotation>$$ Delta $$</annotation>\u0000 </semantics></math>-potential in nuclear matter. A comparison of our results with those obtained for nonrotating stars shows that the maximum mass difference between differentially rotating and static stars is independent of the underlying particle composition of the star. We further find that the decrease in the radii and increase in the maximum masses of stellar models when <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>Δ</mi>\u0000 </mrow>\u0000 <annotation>$$ Delta $$</annotation>\u0000 </semantics></math>-isobars are added to hyperonuclear matter (as initially observed for static and uniformly rotating stars) persist also in the case of differentially rotating neutron stars.</p>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"345 2-3","pages":""},"PeriodicalIF":0.9,"publicationDate":"2023-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asna.20230160","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138530371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Circumstellar disk and the first generation of stars 星周盘和第一代恒星
IF 0.9 4区 物理与天体物理
Astronomische Nachrichten Pub Date : 2023-12-03 DOI: 10.1002/asna.20230150
Rafeel Riaz
{"title":"Circumstellar disk and the first generation of stars","authors":"Rafeel Riaz","doi":"10.1002/asna.20230150","DOIUrl":"10.1002/asna.20230150","url":null,"abstract":"&lt;p&gt;Circumstellar disk (CD) around the first generation of stars have been numerically investigated here to see if the cooling regimes also play a role in the formation and evolution of the disk associated with the most massive protostars (MMPS). Also, an emphasis is given to exploring the effect of the initial turbulent motion of the metal-free gas on the resulting morphology of the CD. For this, a systematic range of Mach number &lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;ℳ&lt;/mi&gt;\u0000 &lt;mo&gt;=&lt;/mo&gt;\u0000 &lt;mn&gt;0&lt;/mn&gt;\u0000 &lt;mo&gt;.&lt;/mo&gt;\u0000 &lt;mn&gt;1&lt;/mn&gt;\u0000 &lt;mo&gt;−&lt;/mo&gt;\u0000 &lt;mn&gt;1&lt;/mn&gt;\u0000 &lt;mo&gt;.&lt;/mo&gt;\u0000 &lt;mn&gt;0&lt;/mn&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ mathcal{M}=0.1-1.0 $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; has been examined. It has been found that the disk-to-star mass ratio &lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;M&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mtext&gt;disk&lt;/mtext&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ {M}_{mathrm{disk}} $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;/&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;M&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mtext&gt;star&lt;/mtext&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ {M}_{mathrm{star}} $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; is larger when the model evolution is based on the first H&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt; &lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mn&gt;2&lt;/mn&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ {}_2 $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; line cooling followed by subsequent cooling via collision-induced emission than in the model where only H&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt; &lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mn&gt;2&lt;/mn&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ {}_2 $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; line cooling remains operative. Also, irrespective of the initial turbulence in the cloud, the former type of model yields a CD as massive as 7.66 M&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mrow&gt;\u0000 ","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"345 2-3","pages":""},"PeriodicalIF":0.9,"publicationDate":"2023-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138542165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Uncertainty relation in viscous hydrodynamics and its effects in collective flow observables 粘性流体力学中的不确定性关系及其对集体流动观测值的影响
IF 0.9 4区 物理与天体物理
Astronomische Nachrichten Pub Date : 2023-12-03 DOI: 10.1002/asna.20230145
G. Gonçalves de Matos, L. Henrique, T. Kodama, T. Koide
{"title":"Uncertainty relation in viscous hydrodynamics and its effects in collective flow observables","authors":"G. Gonçalves de Matos,&nbsp;L. Henrique,&nbsp;T. Kodama,&nbsp;T. Koide","doi":"10.1002/asna.20230145","DOIUrl":"10.1002/asna.20230145","url":null,"abstract":"<p>The uncertainty relation is considered to be one of key features of quantum mechanics which distinguishes quantum and classical systems. Recently, we developed a new formulation of the uncertainty relation based on the generalized scheme of variational principle, the stochastic variational method (SVM). In this method, the uncertainty relation is related to the nondifferentiability of observables and thus can be obtained even in classical stochastic systems. This new formulation resolves the famous paradox in quantum mechanics, the angular uncertainty relation without introducing artificial assumptions. In this paper, we show that the fluctuations of position and momentum for a nonrelativistic viscous fluid element satisfies the uncertainty relation analogous to the corresponding quantum mechanical one. Such a fluctuation is sensitive to the temperature gradient at the freezeout surface and can affect the collective flow anisotropy in relativistic heavy-ion collisions.</p>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"345 2-3","pages":""},"PeriodicalIF":0.9,"publicationDate":"2023-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138530362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Decomposition of the central structure of NGC 2273 in the NIR: A case study ngc2273中心结构在近红外波段的分解:一个个案研究
IF 0.9 4区 物理与天体物理
Astronomische Nachrichten Pub Date : 2023-11-27 DOI: 10.1002/asna.20230094
L. Schey, J. Heidt, A. Pramskiy, D. Thompson, G. Agapito, S. Esposito, R. Gredel, D. Miller, E. Pinna, A. Puglisi, F. Rossi, W. Seifert, G. Taylor, A. Quirrenbach
{"title":"Decomposition of the central structure of NGC 2273 in the NIR: A case study","authors":"L. Schey, J. Heidt, A. Pramskiy, D. Thompson, G. Agapito, S. Esposito, R. Gredel, D. Miller, E. Pinna, A. Puglisi, F. Rossi, W. Seifert, G. Taylor, A. Quirrenbach","doi":"10.1002/asna.20230094","DOIUrl":"https://doi.org/10.1002/asna.20230094","url":null,"abstract":"The Seyfert 2 galaxy NGC 2273 is a prime target to explore how active nuclei can be fed. It has a star-forming innermost nuclear ring with a radius of 0.33kpc from where material may be funneled to the supermassive black hole in its center. In this article, we discuss high-resolution adaptive optics aided JHKs images of NGC 2273 taken with the Large Binocular Telescope. Using Galfit we decomposed the innermost part of NGC 2273 into a core, a disk, and a ring using 58 parameters, 44 of them were used to describe the ring. The stellar mass of the ring was found to be 12 <math altimg=\"urn:x-wiley:asna:media:asna20230094:asna20230094-math-0001\" display=\"inline\" location=\"graphic/asna20230094-math-0001.png\" overflow=\"scroll\">\u0000<semantics>\u0000<mrow>\u0000<mo form=\"prefix\">×</mo>\u0000<mn>1</mn>\u0000<msup>\u0000<mrow>\u0000<mn>0</mn>\u0000</mrow>\u0000<mrow>\u0000<mn>8</mn>\u0000</mrow>\u0000</msup>\u0000<msub>\u0000<mrow>\u0000<mi mathvariant=\"normal\">M</mi>\u0000</mrow>\u0000<mrow>\u0000<mo>⊙</mo>\u0000</mrow>\u0000</msub>\u0000</mrow>\u0000$$ times 1{0}^8{mathrm{M}}_{odot } $$</annotation>\u0000</semantics></math>, a factor of 10 higher than its molecular gas mass. A continuous gas flow via the main stellar bar of NGC 2273 during the lifetime of the bar of up to 10 <math altimg=\"urn:x-wiley:asna:media:asna20230094:asna20230094-math-0002\" display=\"inline\" location=\"graphic/asna20230094-math-0002.png\" overflow=\"scroll\">\u0000<semantics>\u0000<mrow>\u0000<msub>\u0000<mrow>\u0000<mi mathvariant=\"normal\">M</mi>\u0000</mrow>\u0000<mrow>\u0000<mo>⊙</mo>\u0000</mrow>\u0000</msub>\u0000<msup>\u0000<mrow>\u0000<mtext>yr</mtext>\u0000</mrow>\u0000<mrow>\u0000<mo form=\"prefix\">−</mo>\u0000<mn>1</mn>\u0000</mrow>\u0000</msup>\u0000</mrow>\u0000$$ {mathrm{M}}_{odot }{mathrm{yr}}^{-1} $$</annotation>\u0000</semantics></math>\u0000is required to provide the fuel for the formation of the stars unless the star formation efficiency is on the order of 10%. This does not affect the fueling of the nuclear source as the amount of molecular gas required for this low-luminosity active galaxy to achieve this is on the order of <math altimg=\"urn:x-wiley:asna:media:asna20230094:asna20230094-math-0003\" display=\"inline\" location=\"graphic/asna20230094-math-0003.png\" overflow=\"scroll\">\u0000<semantics>\u0000<mrow>\u0000<mn>1</mn>\u0000<msup>\u0000<mrow>\u0000<mn>0</mn>\u0000</mrow>\u0000<mrow>\u0000<mn>4</mn>\u0000</mrow>\u0000</msup>\u0000<msub>\u0000<mrow>\u0000<mi mathvariant=\"normal\">M</mi>\u0000</mrow>\u0000<mrow>\u0000<mo>⊙</mo>\u0000</mrow>\u0000</msub>\u0000</mrow>\u0000$$ 1{0}^4{mathrm{M}}_{odot } $$</annotation>\u0000</semantics></math> only.","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"37 7","pages":""},"PeriodicalIF":0.9,"publicationDate":"2023-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138509353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Possible stellar asterisms carved on a protohistoric stone 刻在史前石头上的可能的恒星
IF 0.9 4区 物理与天体物理
Astronomische Nachrichten Pub Date : 2023-11-22 DOI: 10.1002/asna.20220108
Paolo Molaro, Federico Bernardini
{"title":"Possible stellar asterisms carved on a protohistoric stone","authors":"Paolo Molaro, Federico Bernardini","doi":"10.1002/asna.20220108","DOIUrl":"https://doi.org/10.1002/asna.20220108","url":null,"abstract":"Chisel marks on a stone uncovered in Rupinpiccolo protohistoric hill fort from north-eastern Italy were suggested to be a representation of the night sky (Bernardini et al. 2022 <i>Documenta Praehistorica XLIX</i>). The patterns of the 29 marks are analyzed here to establish if they reproduce popular stellar asterisms. Nine marks are found to match the Tail of Scorpius and five the Orion's Belt, together with Rigel and Betelgeuse. Nine marks are found in the approximate position of the Pleiades showing some match with the cluster members. On the back side, 5 marks possibly reproduce Cassiopeia. One mark slightly North of Orion cannot be identified. The 28 marks show a Pearson correlation coefficient <math altimg=\"urn:x-wiley:asna:media:asna20220108:asna20220108-math-0001\" display=\"inline\" location=\"graphic/asna20220108-math-0001.png\" overflow=\"scroll\">\u0000<semantics>\u0000<mrow>\u0000<mi>r</mi>\u0000</mrow>\u0000$$ r $$</annotation>\u0000</semantics></math>(28) with stellar positions higher than 0.99 with a probability <math altimg=\"urn:x-wiley:asna:media:asna20220108:asna20220108-math-0002\" display=\"inline\" location=\"graphic/asna20220108-math-0002.png\" overflow=\"scroll\">\u0000<semantics>\u0000<mrow>\u0000<mi>p</mi>\u0000</mrow>\u0000$$ p $$</annotation>\u0000</semantics></math> of a wrong correlation lower than 0.001. Departures are about one degree, or about 7 mm, as the mean diameter of the marks, which suggests a manufacturing limitation in the charting. The fort dates <math altimg=\"urn:x-wiley:asna:media:asna20220108:asna20220108-math-0003\" display=\"inline\" location=\"graphic/asna20220108-math-0003.png\" overflow=\"scroll\">\u0000<semantics>\u0000<mrow>\u0000<mo form=\"prefix\">≈</mo>\u0000</mrow>\u0000$$ approx $$</annotation>\u0000</semantics></math>1800–400 BCE when Scorpius and Orion showed about the same orientation at the heliacal rising. The unidentified mark challenges the whole picture. We suggest it could have been the progenitor of a failed supernova, thus offering also the possibility of a verification.","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"36 7","pages":""},"PeriodicalIF":0.9,"publicationDate":"2023-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138509354","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Solid-state curved focal plane arrays realized with simple approaches for compact and high-performance optical systems 用简单的方法实现了用于紧凑和高性能光学系统的固态弯曲焦平面阵列
IF 0.9 4区 物理与天体物理
Astronomische Nachrichten Pub Date : 2023-11-14 DOI: 10.1002/asna.20230135
Shouleh Nikzad, Todd J. Jones, Michael E. Hoenk, Paul von Allmen
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引用次数: 0
CCD imagers for the Transiting Exoplanet Survey Satellite from benchtop to space environment 越轨系外行星巡天卫星的 CCD 成像仪从台式到太空环境
IF 0.9 4区 物理与天体物理
Astronomische Nachrichten Pub Date : 2023-11-02 DOI: 10.1002/asna.20230139
Vyshnavi Suntharalingam, Ilya Prigozhin, Keith Warner, Douglas Young, Deborah Woods, Gregory Berthiaume
{"title":"CCD imagers for the Transiting Exoplanet Survey Satellite from benchtop to space environment","authors":"Vyshnavi Suntharalingam,&nbsp;Ilya Prigozhin,&nbsp;Keith Warner,&nbsp;Douglas Young,&nbsp;Deborah Woods,&nbsp;Gregory Berthiaume","doi":"10.1002/asna.20230139","DOIUrl":"10.1002/asna.20230139","url":null,"abstract":"<p>The Transiting Exoplanet Survey Satellite (TESS) is a Massachusetts Institute of Technology-led NASA Explorer-class mission planned to spend 2 years discovering transiting exoplanets by an all-sky survey. The observatory contains four wide field-of-view camera systems for a total of 16.8 Megapixel, low-noise, low-power CCD detectors. Now over 5 years beyond its launch date and 10 years after the CCD design tape out, we report on our approach for managing camera system development, with particular emphasis on the design, fabrication, and testing of the silicon detectors, developed on 200-mm high-resistivity wafer substrates. Finally, we present implications of the CCD manufacture observed in the on-orbit performance.</p>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"344 8-9","pages":""},"PeriodicalIF":0.9,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asna.20230139","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135933886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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