Hola,<div><br></div><div>aca va el anuncio oficial, en Mayo debería confirmarse si ese es el origen del efecto, ciertamente un poco mas mundano que la mayoría de las especulaciones que se presentaron para explicarlo en los últimos meses :)</div>
<div><br></div><div>Saludos,</div><div>Daniel</div><div><br></div><div><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium">Dear Colleagues,</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium"><br>
</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium"><br></span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium"><br></span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium">The OPERA collaboration has informed its funding agencies and host</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium"><br>
</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium">laboratories that it has identified two possible effects that could have an</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium"><br>
</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium">influence on its neutrino timing measurement. These both require further</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium"><br>
</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium">tests with a short pulsed beam. If confirmed, one would increase the size of</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium"><br>
</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium">the measured effect, the other would diminish it. The first possible effect</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium"><br>
</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium">concerns an oscillator used to provide the time stamps for GPS</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium"><br>
</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium">synchronizations. It could have led to an overestimate of the neutrino's</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium"><br>
</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium">time of flight. The second concerns the optical fibre connector that brings</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium"><br>
</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium">the external GPS signal to the OPERA master clock, which may not have been</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium"><br>
</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium">functioning correctly when the measurements were taken. If this is the case,</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium"><br>
</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium">it could have led to an underestimate of the time of flight of the</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium"><br>
</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium">neutrinos. The potential extent of these two effects is being studied by the</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium"><br>
</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium">OPERA collaboration. New measurements with short pulsed beams are scheduled</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium"><br>
</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium">for May.</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium"><br></span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium"><br>
</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium"><br></span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium">Best regards,</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium"><br>
</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium"><br></span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium">Rolf Heuer</span><span class="Apple-style-span" style="font-family:Helvetica;font-size:medium"><br>
</span><br><div class="gmail_quote">El 22 de febrero de 2012 19:05, <span dir="ltr"><<a href="mailto:paz@df.uba.ar">paz@df.uba.ar</a>></span> escribió:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Estimados,<br>
<br>
Hace unos meses se reporto que el experimento Opera habia detectado que los neutrinos viajaban a velocidad mayor que la de la luz. El tiempo de llegada de los neutrinos desde su emision en el Cern hasta el detector de Opera era 60 nseg mas que lo admitido por la teoria de la relatividad. Mucha tinta corrio desde ese entonces. Ahora, al al parecer hay fuertes indicios sobre la existencia de un error sistematico en el experimento... Pueden leer la noticia en el portal de la revista Science (el link esta abajo). Segun se informa hoy, los famosos 60 nanosegundos se explican por una falla en la conexion de un cable de fibra optica que iba desde el receptor del GPS a una plaqueta de adquisicion en una computadora... Si esto es cierto es como para reir. A veces asi avanza la ciencia! Si alguien sabe algo mas sobre esto avisen.. Saludos,<br>
<br>
Juan Pablo<br>
<br>
<a href="http://news.sciencemag.org/scienceinsider/2012/02/breaking-news-error-undoes-faster.html?rss=1&utm_source=twitterfeed&utm_medium=twitter#.T0VAu8O-G8w.twitter" target="_blank">http://news.sciencemag.org/<u></u>scienceinsider/2012/02/<u></u>breaking-news-error-undoes-<u></u>faster.html?rss=1&utm_source=<u></u>twitterfeed&utm_medium=<u></u>twitter#.T0VAu8O-G8w.twitter</a><br>
<br>
<br>
<br>
<br>
Dr Juan Pablo Paz<br>
Profesor Titular UBA, Investigador Principal CONICET<br>
Departamento de Fisica & Instituto de Fisica de Buenos Aires<br>
FCEyN UBA, Pabellon 1, Ciudad Universitaria<br>
1428 Buenos Aires, Argentina<br>
Email: <a href="mailto:paz@df.uba.ar" target="_blank">paz@df.uba.ar</a><br>
Phone: +54-11-45763353<br>
<a href="http://www.df.uba.ar/users/paz" target="_blank">http://www.df.uba.ar/users/paz</a><br>
<a href="http://www.qufiba.df.uba.ar" target="_blank">http://www.qufiba.df.uba.ar</a><br>
<br>
</blockquote></div><br><br clear="all"><div><br></div>-- <br>Daniel de Florian<br>
</div>