Serveur d'exploration sur les relations entre la France et l'Australie

Attention, ce site est en cours de développement !
Attention, site généré par des moyens informatiques à partir de corpus bruts.
Les informations ne sont donc pas validées.

A spectroscopic survey of EC4, an extended cluster in Andromeda's halo

Identifieur interne : 007F36 ( Main/Exploration ); précédent : 007F35; suivant : 007F37

A spectroscopic survey of EC4, an extended cluster in Andromeda's halo

Auteurs : M. L. M. Collins [Royaume-Uni] ; S. C. Chapman ; M. Irwin ; R. Ibata [France] ; N. F. Martin [Allemagne] ; A. M. N. Ferguson [Royaume-Uni] ; A. Huxor ; G. F. Lewis [Australie] ; A. D. Mackey [Royaume-Uni] ; A. W. Mcconnachie [Canada] ; N. Tanvir

Source :

RBID : ISTEX:F022D36DBC3BCFDFE07609F45D1A308778BDF102

Descripteurs français

English descriptors

Abstract

We present a spectroscopic survey of candidate red giant branch stars in the extended star cluster, EC4, discovered in the halo of M31 from our Canada—France—Hawaii Telescope/MegaCam survey, overlapping the tidal streams, Streams ‘Cp’ and ‘Cr’. These observations used the DEep Imaging Multi‐Object Spectrograph mounted on the Keck II telescope to obtain spectra around the Caii triplet region with ∼1.3 Å resolution. Six stars lying on the red giant branch within two core radii of the centre of EC4 are found to have an average vr=−287.9+1.9−2.4 km s−1 and σv,corr = 2.7+4.2−2.7 km s−1, taking instrumental errors into account. The resulting mass‐to‐light ratio for EC4 is M/L = 6.7+15−6.7 M⊙/L⊙, a value that is consistent with a globular cluster within the 1σ errors we derive. From the summed spectra of our member stars, we find EC4 to be metal‐poor, with [Fe/H]=−1.6 ± 0.15. We discuss several formation and evolution scenarios which could account for our kinematic and metallicity constraints on EC4, and conclude that EC4 is most comparable with an extended globular cluster. We also compare the kinematics and metallicity of EC4 with Streams ‘Cp’ and ‘Cr’, and find that EC4 bears a striking resemblance to Stream ‘Cp’ in terms of velocity, and that the two structures are identical in terms of both their spectroscopic and photometric metallicities. From this, we conclude that EC4 is likely related to Stream ‘Cp’.

Url:
DOI: 10.1111/j.1365-2966.2009.14830.x


Affiliations:


Links toward previous steps (curation, corpus...)


Le document en format XML

<record>
<TEI wicri:istexFullTextTei="biblStruct">
<teiHeader>
<fileDesc>
<titleStmt>
<title xml:lang="en">A spectroscopic survey of EC4, an extended cluster in Andromeda's halo</title>
<author>
<name sortKey="Collins, M L M" sort="Collins, M L M" uniqKey="Collins M" first="M. L. M." last="Collins">M. L. M. Collins</name>
</author>
<author>
<name sortKey="Chapman, S C" sort="Chapman, S C" uniqKey="Chapman S" first="S. C." last="Chapman">S. C. Chapman</name>
</author>
<author>
<name sortKey="Irwin, M" sort="Irwin, M" uniqKey="Irwin M" first="M." last="Irwin">M. Irwin</name>
</author>
<author>
<name sortKey="Ibata, R" sort="Ibata, R" uniqKey="Ibata R" first="R." last="Ibata">R. Ibata</name>
</author>
<author>
<name sortKey="Martin, N F" sort="Martin, N F" uniqKey="Martin N" first="N. F." last="Martin">N. F. Martin</name>
</author>
<author>
<name sortKey="Ferguson, A M N" sort="Ferguson, A M N" uniqKey="Ferguson A" first="A. M. N." last="Ferguson">A. M. N. Ferguson</name>
</author>
<author>
<name sortKey="Huxor, A" sort="Huxor, A" uniqKey="Huxor A" first="A." last="Huxor">A. Huxor</name>
</author>
<author>
<name sortKey="Lewis, G F" sort="Lewis, G F" uniqKey="Lewis G" first="G. F." last="Lewis">G. F. Lewis</name>
</author>
<author>
<name sortKey="Mackey, A D" sort="Mackey, A D" uniqKey="Mackey A" first="A. D." last="Mackey">A. D. Mackey</name>
</author>
<author>
<name sortKey="Mcconnachie, A W" sort="Mcconnachie, A W" uniqKey="Mcconnachie A" first="A. W." last="Mcconnachie">A. W. Mcconnachie</name>
</author>
<author>
<name sortKey="Tanvir, N" sort="Tanvir, N" uniqKey="Tanvir N" first="N." last="Tanvir">N. Tanvir</name>
</author>
</titleStmt>
<publicationStmt>
<idno type="wicri:source">ISTEX</idno>
<idno type="RBID">ISTEX:F022D36DBC3BCFDFE07609F45D1A308778BDF102</idno>
<date when="2009" year="2009">2009</date>
<idno type="doi">10.1111/j.1365-2966.2009.14830.x</idno>
<idno type="url">https://api.istex.fr/document/F022D36DBC3BCFDFE07609F45D1A308778BDF102/fulltext/pdf</idno>
<idno type="wicri:Area/Istex/Corpus">002D25</idno>
<idno type="wicri:explorRef" wicri:stream="Istex" wicri:step="Corpus" wicri:corpus="ISTEX">002D25</idno>
<idno type="wicri:Area/Istex/Curation">002D25</idno>
<idno type="wicri:Area/Istex/Checkpoint">000F73</idno>
<idno type="wicri:explorRef" wicri:stream="Istex" wicri:step="Checkpoint">000F73</idno>
<idno type="wicri:doubleKey">0035-8711:2009:Collins M:a:spectroscopic:survey</idno>
<idno type="wicri:source">ISTEX</idno>
<idno type="RBID">ISTEX:65971852B90429D6FE5F716EF9CCFB24B551DBB8</idno>
<idno type="url">https://api.istex.fr/document/65971852B90429D6FE5F716EF9CCFB24B551DBB8/fulltext/pdf</idno>
<idno type="wicri:Area/Istex/Corpus">001310</idno>
<idno type="wicri:explorRef" wicri:stream="Istex" wicri:step="Corpus" wicri:corpus="ISTEX">001310</idno>
<idno type="wicri:Area/Istex/Curation">001310</idno>
<idno type="wicri:Area/Istex/Checkpoint">000D64</idno>
<idno type="wicri:explorRef" wicri:stream="Istex" wicri:step="Checkpoint">000D64</idno>
<idno type="wicri:doubleKey">0035-8711:2009:Collins M:a:spectroscopic:survey</idno>
<idno type="wicri:Area/Main/Merge">008631</idno>
<idno type="wicri:source">INIST</idno>
<idno type="RBID">Pascal:09-0277069</idno>
<idno type="wicri:Area/PascalFrancis/Corpus">002D40</idno>
<idno type="wicri:Area/PascalFrancis/Curation">003280</idno>
<idno type="wicri:Area/PascalFrancis/Checkpoint">002D16</idno>
<idno type="wicri:explorRef" wicri:stream="PascalFrancis" wicri:step="Checkpoint">002D16</idno>
<idno type="wicri:doubleKey">0035-8711:2009:Collins M:a:spectroscopic:survey</idno>
<idno type="wicri:Area/Main/Merge">008C85</idno>
<idno type="wicri:Area/Main/Curation">007F36</idno>
<idno type="wicri:Area/Main/Exploration">007F36</idno>
</publicationStmt>
<sourceDesc>
<biblStruct>
<analytic>
<title level="a" type="main">A spectroscopic survey of EC4, an extended cluster in Andromeda's halo
<ref type="note" target="#fn2">
<hi rend="superscript"></hi>
</ref>
</title>
<author>
<name sortKey="Collins, M L M" sort="Collins, M L M" uniqKey="Collins M" first="M. L. M." last="Collins">M. L. M. Collins</name>
<affiliation></affiliation>
<affiliation wicri:level="1">
<country wicri:rule="url">Royaume-Uni</country>
</affiliation>
</author>
<author>
<name sortKey="Chapman, S C" sort="Chapman, S C" uniqKey="Chapman S" first="S. C." last="Chapman">S. C. Chapman</name>
<affiliation>
<wicri:noCountry code="subField">0HA</wicri:noCountry>
</affiliation>
</author>
<author>
<name sortKey="Irwin, M" sort="Irwin, M" uniqKey="Irwin M" first="M." last="Irwin">M. Irwin</name>
<affiliation>
<wicri:noCountry code="subField">0HA</wicri:noCountry>
</affiliation>
</author>
<author>
<name sortKey="Ibata, R" sort="Ibata, R" uniqKey="Ibata R" first="R." last="Ibata">R. Ibata</name>
<affiliation wicri:level="1">
<country xml:lang="fr">France</country>
<wicri:regionArea>Observatoire de Strasbourg, 11 rue de l'Université, F‐67000 Strasbourg</wicri:regionArea>
<wicri:noRegion>67000 Strasbourg</wicri:noRegion>
<wicri:noRegion>F‐67000 Strasbourg</wicri:noRegion>
</affiliation>
</author>
<author>
<name sortKey="Martin, N F" sort="Martin, N F" uniqKey="Martin N" first="N. F." last="Martin">N. F. Martin</name>
<affiliation wicri:level="3">
<country xml:lang="fr">Allemagne</country>
<wicri:regionArea>Max‐Planck‐Institut für Astronomie, Königstuhl 17, D‐69117 Heidelberg</wicri:regionArea>
<placeName>
<region type="land" nuts="1">Bade-Wurtemberg</region>
<region type="district" nuts="2">District de Karlsruhe</region>
<settlement type="city">Heidelberg</settlement>
</placeName>
</affiliation>
</author>
<author>
<name sortKey="Ferguson, A M N" sort="Ferguson, A M N" uniqKey="Ferguson A" first="A. M. N." last="Ferguson">A. M. N. Ferguson</name>
<affiliation wicri:level="4">
<orgName type="university">Université d'Édimbourg</orgName>
<country>Royaume-Uni</country>
<placeName>
<settlement type="city">Édimbourg</settlement>
<region type="country">Écosse</region>
</placeName>
</affiliation>
</author>
<author>
<name sortKey="Huxor, A" sort="Huxor, A" uniqKey="Huxor A" first="A." last="Huxor">A. Huxor</name>
<affiliation>
<wicri:noCountry code="subField">1TL</wicri:noCountry>
</affiliation>
</author>
<author>
<name sortKey="Lewis, G F" sort="Lewis, G F" uniqKey="Lewis G" first="G. F." last="Lewis">G. F. Lewis</name>
<affiliation wicri:level="4">
<country xml:lang="fr">Australie</country>
<wicri:regionArea>Sydney Institute for Astronomy, School of Physics, A29, University of Sydney, NSW 2006</wicri:regionArea>
<orgName type="university">Université de Sydney</orgName>
<placeName>
<settlement type="city">Sydney</settlement>
<region type="état">Nouvelle-Galles du Sud</region>
</placeName>
</affiliation>
</author>
<author>
<name sortKey="Mackey, A D" sort="Mackey, A D" uniqKey="Mackey A" first="A. D." last="Mackey">A. D. Mackey</name>
<affiliation wicri:level="4">
<orgName type="university">Université d'Édimbourg</orgName>
<country>Royaume-Uni</country>
<placeName>
<settlement type="city">Édimbourg</settlement>
<region type="country">Écosse</region>
</placeName>
</affiliation>
</author>
<author>
<name sortKey="Mcconnachie, A W" sort="Mcconnachie, A W" uniqKey="Mcconnachie A" first="A. W." last="Mcconnachie">A. W. Mcconnachie</name>
<affiliation wicri:level="1">
<country xml:lang="fr">Canada</country>
<wicri:regionArea>NRC Herzberg Institute of Astrophysics, 5071 West Saanich Road, Victoria V9E 2E7</wicri:regionArea>
<wicri:noRegion>Victoria V9E 2E7</wicri:noRegion>
</affiliation>
</author>
<author>
<name sortKey="Tanvir, N" sort="Tanvir, N" uniqKey="Tanvir N" first="N." last="Tanvir">N. Tanvir</name>
<affiliation>
<wicri:noCountry code="subField">LE17RH</wicri:noCountry>
</affiliation>
</author>
</analytic>
<monogr></monogr>
<series>
<title level="j" type="main">Monthly Notices of the Royal Astronomical Society</title>
<title level="j" type="alt">MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY</title>
<idno type="ISSN">0035-8711</idno>
<idno type="eISSN">1365-2966</idno>
<imprint>
<biblScope unit="vol">396</biblScope>
<biblScope unit="issue">3</biblScope>
<biblScope unit="page" from="1619">1619</biblScope>
<biblScope unit="page" to="1628">1628</biblScope>
<biblScope unit="page-count">10</biblScope>
<publisher>Blackwell Publishing Ltd</publisher>
<pubPlace>Oxford, UK</pubPlace>
<date type="published" when="2009-07-01">2009-07-01</date>
</imprint>
<idno type="ISSN">0035-8711</idno>
</series>
</biblStruct>
</sourceDesc>
<seriesStmt>
<idno type="ISSN">0035-8711</idno>
</seriesStmt>
</fileDesc>
<profileDesc>
<textClass>
<keywords scheme="KwdEn" xml:lang="en">
<term>Belokurov</term>
<term>Central surface brightness</term>
<term>Central velocity dispersion</term>
<term>Centre</term>
<term>Cluster centre</term>
<term>Core radii</term>
<term>Dark matter</term>
<term>Dartmouth isochrones</term>
<term>Deep imaging spectrograph</term>
<term>Deimos</term>
<term>Dispersion</term>
<term>Dsph population</term>
<term>Dsphs</term>
<term>Dwarf</term>
<term>Dwarf galaxies</term>
<term>Dwarf galaxy</term>
<term>Dwarf spheroidal</term>
<term>Eld</term>
<term>Extreme tail</term>
<term>Galaxies</term>
<term>Galaxy</term>
<term>Galaxy clusters</term>
<term>Gaussian centred</term>
<term>Giant branch</term>
<term>Giant stars</term>
<term>Globular cluster</term>
<term>Globular clusters</term>
<term>Guhathakurta</term>
<term>Halo</term>
<term>Histogram</term>
<term>Huxor</term>
<term>Ibata</term>
<term>Individual spectra</term>
<term>Irwin</term>
<term>Isochrone</term>
<term>Journal compilation</term>
<term>Kinematics</term>
<term>Likely members</term>
<term>Local group</term>
<term>Lognormal size distribution</term>
<term>Luminosity</term>
<term>Mackey</term>
<term>Mass to light ratio</term>
<term>Matter component</term>
<term>Mcconnachie</term>
<term>Mcconnachie irwin</term>
<term>Member star</term>
<term>Member stars</term>
<term>Metallicities</term>
<term>Metallicity</term>
<term>Metallicity comparison</term>
<term>Mnras</term>
<term>Model atmosphere spectrum</term>
<term>More metal</term>
<term>Other parameter</term>
<term>Parameter range</term>
<term>Parameter space</term>
<term>Photometric</term>
<term>Photometric metallicities</term>
<term>Probability distribution</term>
<term>Progenitor</term>
<term>Radial velocities</term>
<term>Radial velocity</term>
<term>Radial velocity uncertainties</term>
<term>Red giant stars</term>
<term>Red stars</term>
<term>Relative likelihood distribution</term>
<term>Richstone tremaine</term>
<term>Similar luminosity</term>
<term>Simon geha</term>
<term>Spectroscopic</term>
<term>Spectroscopic candidates</term>
<term>Spectroscopic masks</term>
<term>Spectroscopic metallicity</term>
<term>Spectroscopic observations</term>
<term>Spectroscopic survey</term>
<term>Star clusters</term>
<term>Stellar</term>
<term>Stellar association</term>
<term>Stellar kinematics</term>
<term>Stellar system</term>
<term>Surface gravity</term>
<term>Tanvir</term>
<term>Target stars</term>
<term>Tentative members</term>
<term>Tidal</term>
<term>Tidal disruption</term>
<term>Tidal radius</term>
<term>Triplets</term>
<term>Velocity difference</term>
<term>Velocity differences</term>
<term>Velocity dispersion</term>
<term>Velocity dispersions</term>
<term>Willman</term>
</keywords>
<keywords scheme="Pascal" xml:lang="fr">
<term>Amas galaxies</term>
<term>Amas globulaire</term>
<term>Amas stellaire</term>
<term>Cinématique stellaire</term>
<term>Etoile géante</term>
<term>Etoile membre</term>
<term>Etoile rouge</term>
<term>Galaxies</term>
<term>Géante rouge</term>
<term>Métallicité</term>
<term>Rapport masse luminosité</term>
<term>Triplet</term>
</keywords>
<keywords scheme="Teeft" xml:lang="en">
<term>Belokurov</term>
<term>Central surface brightness</term>
<term>Central velocity dispersion</term>
<term>Centre</term>
<term>Cluster centre</term>
<term>Core radii</term>
<term>Dark matter</term>
<term>Dartmouth isochrones</term>
<term>Deep imaging spectrograph</term>
<term>Deimos</term>
<term>Dispersion</term>
<term>Dsph population</term>
<term>Dsphs</term>
<term>Dwarf</term>
<term>Dwarf galaxies</term>
<term>Dwarf galaxy</term>
<term>Dwarf spheroidal</term>
<term>Eld</term>
<term>Extreme tail</term>
<term>Galaxy</term>
<term>Gaussian centred</term>
<term>Giant branch</term>
<term>Globular cluster</term>
<term>Guhathakurta</term>
<term>Halo</term>
<term>Histogram</term>
<term>Huxor</term>
<term>Ibata</term>
<term>Individual spectra</term>
<term>Irwin</term>
<term>Isochrone</term>
<term>Journal compilation</term>
<term>Kinematics</term>
<term>Likely members</term>
<term>Local group</term>
<term>Lognormal size distribution</term>
<term>Luminosity</term>
<term>Mackey</term>
<term>Matter component</term>
<term>Mcconnachie</term>
<term>Mcconnachie irwin</term>
<term>Member star</term>
<term>Member stars</term>
<term>Metallicities</term>
<term>Metallicity</term>
<term>Metallicity comparison</term>
<term>Mnras</term>
<term>Model atmosphere spectrum</term>
<term>More metal</term>
<term>Other parameter</term>
<term>Parameter range</term>
<term>Parameter space</term>
<term>Photometric</term>
<term>Photometric metallicities</term>
<term>Probability distribution</term>
<term>Progenitor</term>
<term>Radial velocities</term>
<term>Radial velocity</term>
<term>Radial velocity uncertainties</term>
<term>Relative likelihood distribution</term>
<term>Richstone tremaine</term>
<term>Similar luminosity</term>
<term>Simon geha</term>
<term>Spectroscopic</term>
<term>Spectroscopic candidates</term>
<term>Spectroscopic masks</term>
<term>Spectroscopic metallicity</term>
<term>Spectroscopic observations</term>
<term>Spectroscopic survey</term>
<term>Stellar</term>
<term>Stellar association</term>
<term>Stellar system</term>
<term>Surface gravity</term>
<term>Tanvir</term>
<term>Target stars</term>
<term>Tentative members</term>
<term>Tidal</term>
<term>Tidal disruption</term>
<term>Tidal radius</term>
<term>Velocity difference</term>
<term>Velocity differences</term>
<term>Velocity dispersion</term>
<term>Velocity dispersions</term>
<term>Willman</term>
</keywords>
</textClass>
</profileDesc>
</teiHeader>
<front>
<div type="abstract" xml:lang="en">We present a spectroscopic survey of candidate red giant branch stars in the extended star cluster, EC4, discovered in the halo of M31 from our Canada—France—Hawaii Telescope/MegaCam survey, overlapping the tidal streams, Streams ‘Cp’ and ‘Cr’. These observations used the DEep Imaging Multi‐Object Spectrograph mounted on the Keck II telescope to obtain spectra around the Caii triplet region with ∼1.3 Å resolution. Six stars lying on the red giant branch within two core radii of the centre of EC4 are found to have an average vr=−287.9+1.9−2.4 km s−1 and σv,corr = 2.7+4.2−2.7 km s−1, taking instrumental errors into account. The resulting mass‐to‐light ratio for EC4 is M/L = 6.7+15−6.7 M⊙/L⊙, a value that is consistent with a globular cluster within the 1σ errors we derive. From the summed spectra of our member stars, we find EC4 to be metal‐poor, with [Fe/H]=−1.6 ± 0.15. We discuss several formation and evolution scenarios which could account for our kinematic and metallicity constraints on EC4, and conclude that EC4 is most comparable with an extended globular cluster. We also compare the kinematics and metallicity of EC4 with Streams ‘Cp’ and ‘Cr’, and find that EC4 bears a striking resemblance to Stream ‘Cp’ in terms of velocity, and that the two structures are identical in terms of both their spectroscopic and photometric metallicities. From this, we conclude that EC4 is likely related to Stream ‘Cp’.</div>
</front>
</TEI>
<affiliations>
<list>
<country>
<li>Allemagne</li>
<li>Australie</li>
<li>Canada</li>
<li>France</li>
<li>Royaume-Uni</li>
</country>
<region>
<li>Bade-Wurtemberg</li>
<li>District de Karlsruhe</li>
<li>Nouvelle-Galles du Sud</li>
<li>Écosse</li>
</region>
<settlement>
<li>Heidelberg</li>
<li>Sydney</li>
<li>Édimbourg</li>
</settlement>
<orgName>
<li>Université d'Édimbourg</li>
<li>Université de Sydney</li>
</orgName>
</list>
<tree>
<noCountry>
<name sortKey="Chapman, S C" sort="Chapman, S C" uniqKey="Chapman S" first="S. C." last="Chapman">S. C. Chapman</name>
<name sortKey="Huxor, A" sort="Huxor, A" uniqKey="Huxor A" first="A." last="Huxor">A. Huxor</name>
<name sortKey="Irwin, M" sort="Irwin, M" uniqKey="Irwin M" first="M." last="Irwin">M. Irwin</name>
<name sortKey="Tanvir, N" sort="Tanvir, N" uniqKey="Tanvir N" first="N." last="Tanvir">N. Tanvir</name>
</noCountry>
<country name="Royaume-Uni">
<noRegion>
<name sortKey="Collins, M L M" sort="Collins, M L M" uniqKey="Collins M" first="M. L. M." last="Collins">M. L. M. Collins</name>
</noRegion>
<name sortKey="Ferguson, A M N" sort="Ferguson, A M N" uniqKey="Ferguson A" first="A. M. N." last="Ferguson">A. M. N. Ferguson</name>
<name sortKey="Mackey, A D" sort="Mackey, A D" uniqKey="Mackey A" first="A. D." last="Mackey">A. D. Mackey</name>
</country>
<country name="France">
<noRegion>
<name sortKey="Ibata, R" sort="Ibata, R" uniqKey="Ibata R" first="R." last="Ibata">R. Ibata</name>
</noRegion>
</country>
<country name="Allemagne">
<region name="Bade-Wurtemberg">
<name sortKey="Martin, N F" sort="Martin, N F" uniqKey="Martin N" first="N. F." last="Martin">N. F. Martin</name>
</region>
</country>
<country name="Australie">
<region name="Nouvelle-Galles du Sud">
<name sortKey="Lewis, G F" sort="Lewis, G F" uniqKey="Lewis G" first="G. F." last="Lewis">G. F. Lewis</name>
</region>
</country>
<country name="Canada">
<noRegion>
<name sortKey="Mcconnachie, A W" sort="Mcconnachie, A W" uniqKey="Mcconnachie A" first="A. W." last="Mcconnachie">A. W. Mcconnachie</name>
</noRegion>
</country>
</tree>
</affiliations>
</record>

Pour manipuler ce document sous Unix (Dilib)

EXPLOR_STEP=$WICRI_ROOT/Wicri/Asie/explor/AustralieFrV1/Data/Main/Exploration
HfdSelect -h $EXPLOR_STEP/biblio.hfd -nk 007F36 | SxmlIndent | more

Ou

HfdSelect -h $EXPLOR_AREA/Data/Main/Exploration/biblio.hfd -nk 007F36 | SxmlIndent | more

Pour mettre un lien sur cette page dans le réseau Wicri

{{Explor lien
   |wiki=    Wicri/Asie
   |area=    AustralieFrV1
   |flux=    Main
   |étape=   Exploration
   |type=    RBID
   |clé=     ISTEX:F022D36DBC3BCFDFE07609F45D1A308778BDF102
   |texte=   A spectroscopic survey of EC4, an extended cluster in Andromeda's halo
}}

Wicri

This area was generated with Dilib version V0.6.33.
Data generation: Tue Dec 5 10:43:12 2017. Site generation: Tue Mar 5 14:07:20 2024