mass of strange quark [Archive]

alistair

May10-04, 05:02 AM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\n\n\n\nWhy is there such a high uncertainty in the mass of the strange quark?\nSome people quote a 50 per cent error - this seems rediculous!\nIs it possible that there is another quark that has a similar mass to\nthe strange that is being produced in particle experiments and causing\nthe\nlarge margin of uncertainty in the mass of the strange quark?\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>Why is there such a high uncertainty in the mass of the strange quark?
Some people quote a 50 per cent error - this seems rediculous!
Is it possible that there is another quark that has a similar mass to
the strange that is being produced in particle experiments and causing
the
large margin of uncertainty in the mass of the strange quark?

Matthew A. Nobes

May11-04, 05:11 AM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>In article <861c1b21.0405081422.6b063171@posting.google.com >, alistair wrote:\n>\n> Why is there such a high uncertainty in the mass of the strange quark?\n\nIt\'s hard to measure quark masses. The trouble is that they are\nnot seen as free particles in nature, so you have to infer their\nmasses from hadronic decays/spectroscopy.\n\nWhat\'s more, they depend on the regularization scheme you\'re using,\nso the value m_{strange} is not unique. Only if you also\ngive your regularization scheme can you give a unique value.\n\n> Some people quote a 50 per cent error - this seems rediculous!\n\nThere are large theory errors. It\'s a hard thing to extract.\n\n> Is it possible that there is another quark that has a similar mass to\n> the strange that is being produced in particle experiments and causing\n> the large margin of uncertainty in the mass of the strange quark?\n\nI highly doubt it, since another intermidate mass quark would cause\ntrouble for the standard model, and lead to a whole new set\nof intermidiate mass hadrons, which have not been observed.\n\nMatthew\n\n--\nmanobes@sdf.lonestar.org\nSDF Public Access UNIX System - http://sdf.lonestar.org\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>In article <861c1b21.0405081422.6b063171@posting.google.com>, alistair wrote:
>
> Why is there such a high uncertainty in the mass of the strange quark?

It's hard to measure quark masses. The trouble is that they are
not seen as free particles in nature, so you have to infer their
masses from hadronic decays/spectroscopy.

What's more, they depend on the regularization scheme you're using,
so the value m_{strange} is not unique. Only if you also
give your regularization scheme can you give a unique value.

> Some people quote a 50 per cent error - this seems rediculous!

There are large theory errors. It's a hard thing to extract.

> Is it possible that there is another quark that has a similar mass to
> the strange that is being produced in particle experiments and causing
> the large margin of uncertainty in the mass of the strange quark?

I highly doubt it, since another intermidate mass quark would cause
trouble for the standard model, and lead to a whole new set
of intermidiate mass hadrons, which have not been observed.

Matthew

--
manobes@sdf.lonestar.org
SDF Public Access UNIX System - http://sdf.lonestar.org

John Anderson

May14-04, 04:10 AM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>alistair wrote:\n\n> Why is there such a high uncertainty in the mass of the strange quark?\n> Some people quote a 50 per cent error - this seems rediculous!\n\nWhy? It depends on the experimental uncertainties.\n\n> Is it possible that there is another quark that has a similar mass to\n> the strange that is being produced in particle experiments and causing\n> the\n> large margin of uncertainty in the mass of the strange quark?\n\nMaybe. But if you think so, then please post some analysis that\nindicates that your interpretation agrees with experiment.\n\nJohn Anderson\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>alistair wrote:

> Why is there such a high uncertainty in the mass of the strange quark?
> Some people quote a 50 per cent error - this seems rediculous!

Why? It depends on the experimental uncertainties.

> Is it possible that there is another quark that has a similar mass to
> the strange that is being produced in particle experiments and causing
> the
> large margin of uncertainty in the mass of the strange quark?

Maybe. But if you think so, then please post some analysis that
indicates that your interpretation agrees with experiment.

John Anderson