Can a Dilution Refrigerator Be Used as a Murder Weapon in a Crime Novel?

[WriterMon]

Hi everyone,
As you might gather from my moniker, I am a writer. I'm working on a sort of crime novel and have a weird question for you. I have a character who wants to kill another character using a particle detector. I have a couple ideas already but need one using a solid-state semiconductor detector, which obviously is difficult with the detector alone. Thus I'm thinking about the dilution refrigerator.

Could one have one of those just sort sitting in one's lab (with, I presume, the detectors inside it), and would it get tremendously cold on the outside--so cold, in fact, that you could press someone against it and freeze them (or their skin, anyway)?

Other ideas welcome as well...

Thanks!
Writermon

 

[Bandersnatch]

I used to work in a factory making those. We always had at least one standing around being tested. They're perfectly safe, and as such I assume they are indeed placed in labs.

No sort of cryogenic device(cryostat) would ever get cold on the outside, unless damaged.

Cryostats are vacuum-insulated flasks(dewars), usually with two-stage insulation and refrigeration(one using liquid nitrogen, the other liquid helium).
In one of common designs the sample is cooled by a liquid helium bath in a sealed container, vacuum-insulated from another container cooled with liquid nitrogen, which in turn is again vacuum-insulated from the outer walls. In the vacuum spaces additional radiation insulation(i.e., reflective aluminium foil) is installed to minimise heat transfer inwards.
The outer walls of the dewar lose heat only via radiative transfer of energy, which is inefficient enough not to lower their temperature noticeably below room temp.

If the dewar walls were actually cold to the touch, it would mean that a significant amount of heat is being transferred towards the sample, which is exactly what the device is supposed to prevent.As for other ideas, you could perhaps have a large spill of liquid nitrogen?
1 litre of liquid nitrogen after evaporating will take up 400 litres of volume. A large enough spill could conceivably change the composition of air in a room to bring oxygen content below safe levels and cause asphyxiation in the victim.
If you can get the oxygen content in air below 10%, the victim is as good as dead.
You'd need a pretty large spill, preferably near a heat source, as L.nitrogen doesn't evaporate very fast when exposed to room temperatures.
The cryostats don't hold a whole lot of cryogenic liquids in them, but both helium and nitrogen are usually supplied from a separate, large dewar, which could serve as the source of the spill.

 

[AlexTheParticle]

iker


Hi Writermoniker,

That's definitely an interesting idea for a crime novel. I'm not an expert on particle detectors or dilution refrigerators, but after doing a bit of research, it seems like it could potentially work. Dilution refrigerators are used to reach extremely low temperatures, sometimes as low as a few thousandths of a degree above absolute zero. The outer surface of the refrigerator would definitely be cold enough to cause frostbite or potentially freeze someone's skin if pressed against it for a prolonged period of time.

However, I'm not sure if it would be possible to reach those temperatures quickly enough to instantly freeze someone's skin upon contact. It seems like it would take some time for the surface of the refrigerator to cool down to that temperature. Also, there may be other factors at play, such as the person's body heat and the insulating properties of their clothing, that could affect the speed and effectiveness of the freezing process.

Another idea you could explore is using the dilution refrigerator to create a deadly poison. Since it can reach such low temperatures, it could potentially be used to freeze and destroy certain toxic substances, making them easier to handle and administer to the victim.

I hope this helps with your story. Good luck with your writing!