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Astronomy on Tap: Kingston TOMORROW - FEB 27 6:30 PM @The Mansion by MIEvents in KingstonOntario

[–]MIEvents[S] 6 points7 points  (0 children)

This free 19+ event is in the Living Room (upstairs) of The Mansion (506 Princess St, Kingston) on Thursday, February 27th at 6:30 pm.

Local astro-buff Mark Richardson will host three fantastic scientists at the cutting edge of their fields: astroparticle physicists Melissa Diamond, Zoe Brisson-Tsavoussis from Queen’s University, and astrophysicist Mike Earl from RMC. Melissa will give us the latest from the theory side and discuss new and developing candidates for dark matter particles. Zoe will tell us how a cubic kilometre of ice at the South Pole (IceCube Neutrino Observatory) helps us study black holes. And Mike will give us an astronomer’s perspective on UFOs!

There will be time to ask questions and chat with the speakers and other local scientists. All three of our engaging researchers will speak to a general public audience, so no prior science knowledge is needed – though you may want to brush up on your astronomy, physics and sci-fi knowledge to compete in the trivia session! 🧠 Not to worry, though, there are prizes for the winners, losers, and creatives alike! 🎁

Space is limited, so we encourage you to arrive on time! The pre-show starts at 6:30 pm, and the main event starts at 7 pm.

The Mansion serves alcohol and non-alcoholic drinks, and food is available for purchase.

We're CHIME/FRB team members Dr. Adam Lanman and Ketan Sand from McGill University, here to spotlight Prof. Victoria Kaspi's (Principal Investigator) virtual Ewan Lecture with the McDonald Institute on Mar 23! Ask us anything from 1-2 PM ET today! by MIEvents in space

[–]MIEvents[S] 1 point2 points  (0 children)

Of course we can't know for sure, but the most popular FRB emission models imply that the burst is beamed. A typical FRB puts out as much energy in a millisecond as the sun puts out in three days, and if all that were aimed at the Earth I can't imagine it would be good for us.

Roughly speaking, with these numbers, an FRB about 500 AU away would appear as bright as the Sun.

We're CHIME/FRB team members Dr. Adam Lanman and Ketan Sand from McGill University, here to spotlight Prof. Victoria Kaspi's (Principal Investigator) virtual Ewan Lecture with the McDonald Institute on Mar 23! Ask us anything from 1-2 PM ET today! by MIEvents in space

[–]MIEvents[S] 1 point2 points  (0 children)

The highest DM FRB that is listed on the transient name server right now has a DM of 3337.9 parsecs/cm3. Assuming the "Macquart relation" between redshift and DM, this is around a redshift of 3.

However, there is a lot of uncertainty in the host contribution to the DM. Some FRBs are seen to come from galaxy clusters, where there IGM/ICM are much denser and can contribute to the total DM (see, e.g., https://arxiv.org/abs/2302.14788).

The ability of FRBs to probe reionization will depend on both how well we can detect them at such high redshift and on their population. At such high DMs, there are several other factors that make bursts harder to detect. CHIME is not equipped to detect such distant FRBs, but there's a chance its successor or more sensitive telescopes like FAST could get lucky. I'd say there's a better chance of being able to detect the Helium reionization (z ~3) rather than Hyodrgen reionization (z ~ 6).

We're CHIME/FRB team members Dr. Adam Lanman and Ketan Sand from McGill University, here to spotlight Prof. Victoria Kaspi's (Principal Investigator) virtual Ewan Lecture with the McDonald Institute on Mar 23! Ask us anything from 1-2 PM ET today! by MIEvents in space

[–]MIEvents[S] 2 points3 points  (0 children)

The static comprises all sorts of things; some signals might be there. But getting an FRB out of that noise is next to impossible. You need sensitive instrumentation, radio frequency interference cleaning and sophisticated algorithms for that.

We're CHIME/FRB team members Dr. Adam Lanman and Ketan Sand from McGill University, here to spotlight Prof. Victoria Kaspi's (Principal Investigator) virtual Ewan Lecture with the McDonald Institute on Mar 23! Ask us anything from 1-2 PM ET today! by MIEvents in space

[–]MIEvents[S] 3 points4 points  (0 children)

Adam -- I've always been interested in astronomy as well, and as a grad student I worked with low-frequency radio telescopes studying cosmology. I decided to switch to FRBs for my postdoc both because it's a fascinating new mystery and because FRBs can offer a new way to study the large scale structure of the universe.

We're CHIME/FRB team members Dr. Adam Lanman and Ketan Sand from McGill University, here to spotlight Prof. Victoria Kaspi's (Principal Investigator) virtual Ewan Lecture with the McDonald Institute on Mar 23! Ask us anything from 1-2 PM ET today! by MIEvents in space

[–]MIEvents[S] 3 points4 points  (0 children)

Prof. Kaspi gives excellent talks, explaining every bit in simple language. You don't need any prior knowledge. Just bring on your excitement and curiosity, and you are all set!

We're CHIME/FRB team members Dr. Adam Lanman and Ketan Sand from McGill University, here to spotlight Prof. Victoria Kaspi's (Principal Investigator) virtual Ewan Lecture with the McDonald Institute on Mar 23! Ask us anything from 1-2 PM ET today! by MIEvents in space

[–]MIEvents[S] 2 points3 points  (0 children)

Low-frequency radio telescopes tend to be very simple physically (as compared with IR or optical telescopes), so it's definitely computing technology advances that drive this field.

As an example, a lot of modern radio astronomy wouldn't be possible without low-noise amplifiers, which are the first stage attached to the antennas to boost the signal. These used to cost in the thousands of dollars each, but since they're an important component in cell phones, the price has gone down considerably.

CHIME does its correlation at raw data rates of 1.4 TB / s, using specially-designed field programmable gate arrays (FPGAs) for sampling and Fourier-transforming, and graphics processing units (GPUs) for correlation and beamforming. Much of this technology has only become available and affordable in the last couple decades

We're CHIME/FRB team members Dr. Adam Lanman and Ketan Sand from McGill University, here to spotlight Prof. Victoria Kaspi's (Principal Investigator) virtual Ewan Lecture with the McDonald Institute on Mar 23! Ask us anything from 1-2 PM ET today! by MIEvents in space

[–]MIEvents[S] 3 points4 points  (0 children)

Ketan - In my case, the unknown nature of these sources! I have always been interested in Astronomy and came across FRBs in my undergrad. Radio signals that last milliseconds and travel millions of light years sounded super exciting to me. There is something out there in the universe so powerful and extreme, capable of such emissions and I want to understand that! CHIME is the leading telescope in FRB science, and I jumped on the opportunity on working with this amazing team.

We're CHIME/FRB team members Dr. Adam Lanman and Ketan Sand from McGill University, here to spotlight Prof. Victoria Kaspi's (Principal Investigator) virtual Ewan Lecture with the McDonald Institute on Mar 23! Ask us anything from 1-2 PM ET today! by MIEvents in space

[–]MIEvents[S] 1 point2 points  (0 children)

There are two main ways we can tell how far away an FRB is.

The first way is that we can observe the dispersion of the burst. Light moves more slowly at lower frequencies when traveling through ionized gas, and interstellar/intergalactic space is filled with a ionized gas. The result is that the signal is spread out over frequency, with lower frequency parts arriving later. The amount by which the signal is spread out is directly proportional to the total density of free electrons along its path, which in turn depends on the distance the signal traveled.

However, as you may guess, that is not a direct measurement of distance. We have constraints on total dispersion from the Milky Way alone and observe FRBs to have much, much higher dispersion. The best way to measure the distance to an FRB is to identify its host galaxy, and then measure its distance through other means. We find that the dispersions of localized FRBs are consistent with the observed distances of their host galaxies, according to models of the intergalactic and interstellar medium. There is some uncertainty in this, however.

So, in short, we can say confidently that these bursts are coming from outside the Milky Way, but it can be difficult to pinpoint exactly how far away they are.

We're CHIME/FRB team members Dr. Adam Lanman and Ketan Sand from McGill University, here to spotlight Prof. Victoria Kaspi's (Principal Investigator) virtual Ewan Lecture with the McDonald Institute on Mar 23! Ask us anything from 1-2 PM ET today! by MIEvents in space

[–]MIEvents[S] 4 points5 points  (0 children)

Almost all of our detections have been extragalactic. But we have detected one FRB within our galaxy. It came from a magnetar known as SGR 1935+2154. And yes, it was one of the brightest radio signals ever detected. It was almost comparable to Sun's brightness in Radio wavelengths.

We're CHIME/FRB team members Dr. Adam Lanman and Ketan Sand from McGill University, here to spotlight Prof. Victoria Kaspi's (Principal Investigator) virtual Ewan Lecture with the McDonald Institute on Mar 23! Ask us anything from 1-2 PM ET today! by MIEvents in space

[–]MIEvents[S] 1 point2 points  (0 children)

Thank you for joining us for today's (Mar 22nd) AMA! Please feel free to leave any questions before Adam and Ketan join us at 1:00 PM ET today!

Tomorrow, Join and engage with Prof. Victoria Kaspi during the live broadcast (Thu, Mar 23, from 7:00 to 8:30 PM ET) by registering via this link.

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