Can we send mail to DL(distribution list)in appian with email smart service in appian

Yes it's possible as long as that distribution list has an email associated to it.

Yeah we have DL which is associated with 8 emails but when we use that DL people in that DL are not getting emails

When you say 8 emails, do you mean you have 8 emails that point to that DL or 8 emails (or users) in that DL?

What I am referring to is a DL with an associated email like analysts@acme.com which contains the individual emails of each analyst.

If that doesn't work, there may be an issue with that DL.

If the DL is just an email address that you could send a normal email to from a normal email account (which is what I assume), and you're sending mails from Appian but the end-recipients aren't getting them, then you will need to check with the administrators of the DL / your email server and see whether the Appian emails are getting Spam Filtered, and add them to a whitelist.

Note this has nothing (or very little) to do with Appian or your implementation within Appian, it's all on the mail-server-side.

If the DL is just an email address that you could send a normal email to from a normal email account (which is what I assume), and you're sending mails from Appian but the end-recipients aren't getting them, then you will need to check with the administrators of the DL / your email server and see whether the Appian emails are getting Spam Filtered, and add them to a whitelist.

Note this has nothing (or very little) to do with Appian or your implementation within Appian, it's all on the mail-server-side.